Bug 1548941 - remove e10s force-enable and force-disable prefs, and on desktop restrict 'normal' e10s pref to automation and unofficial builds, r=bholley,ahal

Differential Revision: https://phabricator.services.mozilla.com/D29892

--HG--
extra : moz-landing-system : lando

build/valgrind/mach_commands.py

@@ -101,6 +101,7 @@ class MachCommands(MachCommandBase):
             env['G_SLICE'] = 'always-malloc'
             env['MOZ_CC_RUN_DURING_SHUTDOWN'] = '1'
             env['MOZ_CRASHREPORTER_NO_REPORT'] = '1'
+            env['MOZ_DISABLE_NONLOCAL_CONNECTIONS'] = '1'
             env['XPCOM_DEBUG_BREAK'] = 'warn'
 
             env.update(self.extra_environment_variables)

testing/gtest/rungtests.py

@@ -96,6 +96,7 @@ class GTests(object):
         env["XPCOM_DEBUG_BREAK"] = "stack-and-abort"
         env["MOZ_CRASHREPORTER_NO_REPORT"] = "1"
         env["MOZ_CRASHREPORTER"] = "1"
+        env["MOZ_DISABLE_NONLOCAL_CONNECTIONS"] = "1"
         env["MOZ_RUN_GTEST"] = "1"
         # Normally we run with GTest default output, override this to use the TBPL test format.
         env["MOZ_TBPL_PARSER"] = "1"

toolkit/xre/nsAppRunner.cpp

@@ -4907,7 +4907,7 @@ bool XRE_Win32kCallsAllowed() {
 
 // If you add anything to this enum, please update about:support to reflect it
 enum {
-  kE10sEnabledByUser = 0,
+  // kE10sEnabledByUser = 0, removed when ending non-e10s support
   kE10sEnabledByDefault = 1,
   kE10sDisabledByUser = 2,
   // kE10sDisabledInSafeMode = 3, was removed in bug 1172491.
@@ -4920,9 +4920,6 @@ enum {
   // kE10sDisabledForOperatingSystem = 10, removed due to xp-eol
 };
 
-const char* kForceEnableE10sPref = "browser.tabs.remote.force-enable";
-const char* kForceDisableE10sPref = "browser.tabs.remote.force-disable";
-
 namespace mozilla {
 
 bool BrowserTabsRemoteAutostart() {
@@ -4937,25 +4934,35 @@ bool BrowserTabsRemoteAutostart() {
     return gBrowserTabsRemoteAutostart;
   }
 
-  bool optInPref = Preferences::GetBool("browser.tabs.remote.autostart", true);
+#if defined(MOZILLA_OFFICIAL) && MOZ_BUILD_APP_IS_BROWSER
+  bool allowSingleProcessOutsideAutomation = false;
+#else
+  bool allowSingleProcessOutsideAutomation = true;
+#endif
+
   int status = kE10sEnabledByDefault;
+  // We use "are non-local connections disabled" as a proxy for
+  // "are we running some kind of automated test". It would be nicer to use
+  // xpc::IsInAutomation(), but that depends on some prefs being set, which
+  // they are not in (at least) gtests (where we can't) and xpcshell.
+  // Long-term, hopefully we can make tests switch to environment variables
+  // to disable e10s and then we can get rid of this.
+  if (allowSingleProcessOutsideAutomation ||
+      xpc::AreNonLocalConnectionsDisabled()) {
+    bool optInPref =
+        Preferences::GetBool("browser.tabs.remote.autostart", true);
 
-  if (optInPref) {
-    gBrowserTabsRemoteAutostart = true;
+    if (optInPref) {
+      gBrowserTabsRemoteAutostart = true;
+    } else {
+      status = kE10sDisabledByUser;
+    }
   } else {
-    status = kE10sDisabledByUser;
-  }
-
-  // Uber override pref for manual testing purposes
-  if (Preferences::GetBool(kForceEnableE10sPref, false)) {
     gBrowserTabsRemoteAutostart = true;
-    status = kE10sEnabledByUser;
   }
 
   // Uber override pref for emergency blocking
-  if (gBrowserTabsRemoteAutostart &&
-      (Preferences::GetBool(kForceDisableE10sPref, false) ||
-       EnvHasValue("MOZ_FORCE_DISABLE_E10S"))) {
+  if (gBrowserTabsRemoteAutostart && EnvHasValue("MOZ_FORCE_DISABLE_E10S")) {
     gBrowserTabsRemoteAutostart = false;
     status = kE10sForceDisabled;
   }