diff --git a/dom/html/test/enableTestPlugin.js b/dom/html/test/enableTestPlugin.js
deleted file mode 100644
index 63c481807e0e..000000000000
--- a/dom/html/test/enableTestPlugin.js
+++ /dev/null
@@ -1,25 +0,0 @@
-// this automatically sets the test plugin to be enabled (not e.g. click-to-play)
-// and resets this afterwards
-
-(function() {
-  function getTestPlugin(aPluginName) {
-    var ph = SpecialPowers.Cc["@mozilla.org/plugin/host;1"]
-                          .getService(SpecialPowers.Ci.nsIPluginHost);
-    var tags = ph.getPluginTags();
-    for (var tag of tags) {
-      if (tag.name == aPluginName) {
-       return tag;
-      }
-    }
-
-    ok(false, "Could not find plugin tag with plugin name '" + name + "'");
-    return null;
-  }
-
-  var plugin = getTestPlugin("Test Plug-in");
-  var oldEnabledState = plugin.enabledState;
-  plugin.enabledState = SpecialPowers.Ci.nsIPluginTag.STATE_ENABLED;
-  SimpleTest.registerCleanupFunction(function() {
-    getTestPlugin("Test Plug-in").enabledState = oldEnabledState;
-  });
-})();
diff --git a/dom/html/test/file_fullscreen-plugins.html b/dom/html/test/file_fullscreen-plugins.html
index b1a99df2be3c..4393dac6bc3d 100644
--- a/dom/html/test/file_fullscreen-plugins.html
+++ b/dom/html/test/file_fullscreen-plugins.html
@@ -16,7 +16,10 @@ Test plugins with DOM full-screen API:
   <title>Test for Bug 545812</title>
   <script type="application/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
   <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
-  <script type="application/javascript" src="enableTestPlugin.js"></script>
+  <script type="application/javascript" src="plugin-utils.js"></script>
+  <script type="application/javascript">
+    setTestPluginEnabledState(SpecialPowers.Ci.nsIPluginTag.STATE_ENABLED);
+  </script>
   <script type="application/javascript" src="file_fullscreen-utils.js"></script>
   <style>
   body:-moz-full-screen, div:-moz-full-screen {
diff --git a/dom/html/test/mochitest.ini b/dom/html/test/mochitest.ini
index 33699d865e54..5be5e0dcd836 100644
--- a/dom/html/test/mochitest.ini
+++ b/dom/html/test/mochitest.ini
@@ -36,7 +36,7 @@ support-files =
   bug499092.html
   bug499092.xml
   bug514856_iframe.html
-  enableTestPlugin.js
+  ../../plugins/test/mochitest/plugin-utils.js
   test_non-ascii-cookie.html^headers^
   file_bug209275_1.html
   file_bug209275_2.html
@@ -482,7 +482,7 @@ skip-if = (buildapp == 'b2g' && toolkit != 'gonk') #time out on b2g desktop spec
 [test_iframe_sandbox_navigation2.html]
 skip-if = (buildapp == 'b2g' && toolkit != 'gonk') #time out on b2g desktop specific
 [test_iframe_sandbox_plugins.html]
-skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' || e10s # b2g(plugins not supported) b2g-debug(plugins not supported) b2g-desktop(plugins not supported)
+skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' # b2g(plugins not supported) b2g-debug(plugins not supported) b2g-desktop(plugins not supported)
 [test_iframe_sandbox_popups.html]
 skip-if = buildapp == 'b2g' # b2g(multiple concurrent window.open()s fail on B2G) b2g-debug(multiple concurrent window.open()s fail on B2G) b2g-desktop(Bug 931116, b2g desktop specific, initial triage)
 [test_iframe_sandbox_popups_inheritance.html]
@@ -512,7 +512,7 @@ skip-if = (buildapp == 'b2g' && (toolkit != 'gonk' || debug)) # b2g-debug(Perma-
 [test_nested_invalid_fieldsets.html]
 [test_object_attributes_reflection.html]
 [test_object_plugin_nav.html]
-skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' || e10s #TIMED_OUT # b2g(plugins not supported) b2g-debug(plugins not supported) b2g-desktop(plugins not supported)
+skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' # b2g(plugins not supported) b2g-debug(plugins not supported) b2g-desktop(plugins not supported)
 [test_ol_attributes_reflection.html]
 [test_option_defaultSelected.html]
 [test_option_selected_state.html]
diff --git a/dom/html/test/test_iframe_sandbox_plugins.html b/dom/html/test/test_iframe_sandbox_plugins.html
index ab38a725c42a..a8c2bd21b7ff 100644
--- a/dom/html/test/test_iframe_sandbox_plugins.html
+++ b/dom/html/test/test_iframe_sandbox_plugins.html
@@ -8,7 +8,10 @@ Implement HTML5 sandbox attribute for IFRAMEs
   <meta charset="utf-8">
   <title>Test for Bug 341604 - plugins</title>
   <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
-  <script type="application/javascript" src="enableTestPlugin.js"></script>
+  <script type="application/javascript" src="plugin-utils.js"></script>
+  <script type="application/javascript">
+    setTestPluginEnabledState(SpecialPowers.Ci.nsIPluginTag.STATE_ENABLED);
+  </script>
   <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
 </head>
 <script type="application/javascript">
diff --git a/dom/html/test/test_object_plugin_nav.html b/dom/html/test/test_object_plugin_nav.html
index 0b5c4984bb43..91590e51afa4 100644
--- a/dom/html/test/test_object_plugin_nav.html
+++ b/dom/html/test/test_object_plugin_nav.html
@@ -8,7 +8,10 @@ https://bugzilla.mozilla.org/show_bug.cgi?id=720130
   <title>Test for Bug 720130</title>
   <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
   <script type="application/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
-  <script type="application/javascript" src="enableTestPlugin.js"></script>
+  <script type="application/javascript" src="plugin-utils.js"></script>
+  <script type="application/javascript">
+    setTestPluginEnabledState(SpecialPowers.Ci.nsIPluginTag.STATE_ENABLED);
+  </script>
   <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
 </head>
 <body>
diff --git a/layout/base/tests/enableTestPlugin.js b/layout/base/tests/enableTestPlugin.js
deleted file mode 100644
index 63c481807e0e..000000000000
--- a/layout/base/tests/enableTestPlugin.js
+++ /dev/null
@@ -1,25 +0,0 @@
-// this automatically sets the test plugin to be enabled (not e.g. click-to-play)
-// and resets this afterwards
-
-(function() {
-  function getTestPlugin(aPluginName) {
-    var ph = SpecialPowers.Cc["@mozilla.org/plugin/host;1"]
-                          .getService(SpecialPowers.Ci.nsIPluginHost);
-    var tags = ph.getPluginTags();
-    for (var tag of tags) {
-      if (tag.name == aPluginName) {
-       return tag;
-      }
-    }
-
-    ok(false, "Could not find plugin tag with plugin name '" + name + "'");
-    return null;
-  }
-
-  var plugin = getTestPlugin("Test Plug-in");
-  var oldEnabledState = plugin.enabledState;
-  plugin.enabledState = SpecialPowers.Ci.nsIPluginTag.STATE_ENABLED;
-  SimpleTest.registerCleanupFunction(function() {
-    getTestPlugin("Test Plug-in").enabledState = oldEnabledState;
-  });
-})();
diff --git a/layout/base/tests/mochitest.ini b/layout/base/tests/mochitest.ini
index 9a65019a5937..c3de8be102df 100644
--- a/layout/base/tests/mochitest.ini
+++ b/layout/base/tests/mochitest.ini
@@ -10,7 +10,7 @@ support-files =
   bug369950-subframe.xml
   file_bug842853.sjs
   file_bug842853.html
-  enableTestPlugin.js
+  ../../../dom/plugins/test/mochitest/plugin-utils.js
   bug558663.html
   bug644768.html
   bug956530-1.html
@@ -178,7 +178,7 @@ skip-if = (buildapp == 'b2g' && toolkit != 'gonk') # bug 1040987
 skip-if = e10s # bug 1020135, nested oop iframes not supported
 support-files = bug921928_event_target_iframe_apps_oop.html
 [test_mozPaintCount.html]
-skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' || e10s # b2g(depends on plugins support) b2g-debug(depends on plugins support) b2g-desktop(depends on plugins support)
+skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' # b2g(depends on plugins support) b2g-debug(depends on plugins support) b2g-desktop(depends on plugins support)
 [test_scroll_event_ordering.html]
 [test_scroll_snapping.html]
 skip-if = buildapp == 'android' # bug 1041833
@@ -192,7 +192,7 @@ support-files = bug968148_inner.html
 [test_bug603550.html]
 skip-if = buildapp == 'b2g' || toolkit == 'android' #TIMED_OUT # b2g(Components.classes[@mozilla.org/widget/dragservice;1] is undefined) b2g-debug(Components.classes[@mozilla.org/widget/dragservice;1] is undefined) b2g-desktop(Components.classes[@mozilla.org/widget/dragservice;1] is undefined)
 [test_bug629838.html]
-skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' || e10s # b2g(depends on plugins support) b2g-debug(depends on plugins support) b2g-desktop(depends on plugins support)
+skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' # b2g(depends on plugins support) b2g-debug(depends on plugins support) b2g-desktop(depends on plugins support)
 [test_bug646757.html]
 [test_bug718809.html]
 [test_bug725426.html]
diff --git a/layout/base/tests/test_bug629838.html b/layout/base/tests/test_bug629838.html
index 16d89607a272..34f12fc168e4 100644
--- a/layout/base/tests/test_bug629838.html
+++ b/layout/base/tests/test_bug629838.html
@@ -3,7 +3,10 @@
 <head>
   <title>Tests for MozAfterPaint</title>
   <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
-  <script type="text/javascript" src="enableTestPlugin.js"></script>
+  <script type="application/javascript" src="plugin-utils.js"></script>
+  <script type="application/javascript">
+    setTestPluginEnabledState(SpecialPowers.Ci.nsIPluginTag.STATE_ENABLED);
+  </script>
   <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
 </head>
 <body>
diff --git a/layout/base/tests/test_mozPaintCount.html b/layout/base/tests/test_mozPaintCount.html
index 4dc3f8f3aafb..4a6c3f71405b 100644
--- a/layout/base/tests/test_mozPaintCount.html
+++ b/layout/base/tests/test_mozPaintCount.html
@@ -3,7 +3,10 @@
 <head>
   <title>Tests for mozPaintCount</title>
   <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
-  <script type="text/javascript" src="enableTestPlugin.js"></script>
+  <script type="application/javascript" src="plugin-utils.js"></script>
+  <script type="application/javascript">
+    setTestPluginEnabledState(SpecialPowers.Ci.nsIPluginTag.STATE_ENABLED);
+  </script>
   <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
 </head>
 <body onload="doBackgroundFlicker()">
diff --git a/layout/generic/test/mochitest.ini b/layout/generic/test/mochitest.ini
index 9e56313ab8ef..32620c2f3d35 100644
--- a/layout/generic/test/mochitest.ini
+++ b/layout/generic/test/mochitest.ini
@@ -3,7 +3,7 @@ skip-if = toolkit == 'android' #CRASH_DUMP, RANDOM, ONLY IN CHUNK 10
 support-files =
   ../../reftests/backgrounds/blue-32x32.png
   ../../reftests/backgrounds/fuchsia-32x32.png
-  ../../base/tests/enableTestPlugin.js
+  ../../../dom/plugins/test/mochitest/plugin-utils.js
   plugin_clipping_helper.xhtml
   plugin_clipping_helper2.xhtml
   plugin_clipping_helper_transformed.xhtml
@@ -104,7 +104,7 @@ skip-if = os=='win'
 [test_image_selection.html]
 [test_image_selection_2.html]
 [test_invalidate_during_plugin_paint.html]
-skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' || e10s # b2g(plugins not supported) b2g-debug(plugins not supported) b2g-desktop(plugins not supported)
+skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' # b2g(plugins not supported) b2g-debug(plugins not supported) b2g-desktop(plugins not supported)
 [test_movement_by_characters.html]
 [test_movement_by_words.html]
 # Disable the caret movement by word test on Linux because the shortcut keys
@@ -124,9 +124,9 @@ skip-if = (buildapp == 'b2g' && toolkit != 'gonk') || e10s #Bug 931116, b2g desk
 [test_plugin_clipping_table.xhtml]
 skip-if = (buildapp == 'b2g' && toolkit != 'gonk') || e10s #Bug 931116, b2g desktop specific, initial triage
 [test_plugin_focus.html]
-skip-if = buildapp == 'mulet' || buildapp == 'b2g' || e10s # b2g(plugins not supported) b2g-debug(plugins not supported) b2g-desktop(plugins not supported)
+skip-if = buildapp == 'mulet' || buildapp == 'b2g' # b2g(plugins not supported) b2g-debug(plugins not supported) b2g-desktop(plugins not supported)
 [test_plugin_mouse_coords.html]
-skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' || e10s # b2g(plugins not supported) b2g-debug(plugins not supported) b2g-desktop(plugins not supported)
+skip-if = buildapp == 'mulet' || buildapp == 'b2g' || toolkit == 'android' # b2g(plugins not supported) b2g-debug(plugins not supported) b2g-desktop(plugins not supported)
 [test_plugin_position.xhtml]
 skip-if = e10s
 [test_scroll_behavior.html]
diff --git a/layout/generic/test/test_invalidate_during_plugin_paint.html b/layout/generic/test/test_invalidate_during_plugin_paint.html
index 820685349b12..5894968b5cc8 100644
--- a/layout/generic/test/test_invalidate_during_plugin_paint.html
+++ b/layout/generic/test/test_invalidate_during_plugin_paint.html
@@ -3,7 +3,10 @@
 <head>
   <title>Test handling plugins invalidating during paint</title>
   <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>    
-  <script type="text/javascript" src="enableTestPlugin.js"></script>
+  <script type="text/javascript" src="plugin-utils.js"></script>
+  <script type="text/javascript">
+    setTestPluginEnabledState(SpecialPowers.Ci.nsIPluginTag.STATE_ENABLED);
+  </script>
   <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
   <style>
   embed { width:200px; height:200px; display:block; }
diff --git a/layout/generic/test/test_plugin_focus.html b/layout/generic/test/test_plugin_focus.html
index 508c8152968f..8c368497cb96 100644
--- a/layout/generic/test/test_plugin_focus.html
+++ b/layout/generic/test/test_plugin_focus.html
@@ -1,7 +1,10 @@
 <html title="Test plugin focus control">
 <head>
   <script type="application/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
-  <script type="text/javascript" src="enableTestPlugin.js"></script>
+  <script type="application/javascript" src="plugin-utils.js"></script>
+  <script type="application/javascript">
+    setTestPluginEnabledState(SpecialPowers.Ci.nsIPluginTag.STATE_ENABLED);
+  </script>
   <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
 </head>
 <body>
diff --git a/layout/generic/test/test_plugin_mouse_coords.html b/layout/generic/test/test_plugin_mouse_coords.html
index b5c71f03673f..cba915ec6ed8 100644
--- a/layout/generic/test/test_plugin_mouse_coords.html
+++ b/layout/generic/test/test_plugin_mouse_coords.html
@@ -4,7 +4,10 @@
   <title>Test delivering mouse events to plugins</title>
   <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>    
   <script type="application/javascript" src="/tests/SimpleTest/EventUtils.js"></script>
-  <script type="text/javascript" src="enableTestPlugin.js"></script>
+  <script type="application/javascript" src="plugin-utils.js"></script>
+  <script type="application/javascript">
+    setTestPluginEnabledState(SpecialPowers.Ci.nsIPluginTag.STATE_ENABLED);
+  </script>
   <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
   <style>
   embed { width:200px; height:200px; display:block; }