From 83753ec77f39a31eddf418d9a6d7106a664bf4d9 Mon Sep 17 00:00:00 2001
From: Robert O'Callahan <robert@ocallahan.org>
Date: Tue, 4 Jan 2011 16:56:05 +1300
Subject: [PATCH] Bug 601064. Ensure we ask each plugin instance to paint at
 least once. Some plugin instances assume they will be asked to paint even if
 they're always invisible. r=bsmedberg,a=blocking

---
 dom/plugins/PluginInstanceChild.cpp | 9 ++++++---
 dom/plugins/PluginInstanceChild.h   | 5 +++++
 2 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/dom/plugins/PluginInstanceChild.cpp b/dom/plugins/PluginInstanceChild.cpp
index 3bd810221a21..1070e1c5eadf 100644
--- a/dom/plugins/PluginInstanceChild.cpp
+++ b/dom/plugins/PluginInstanceChild.cpp
@@ -143,6 +143,7 @@ PluginInstanceChild::PluginInstanceChild(const NPPluginFuncs* aPluginIface)
     , mCurrentAsyncSetWindowTask(nsnull)
     , mPendingPluginCall(false)
     , mDoAlphaExtraction(false)
+    , mHasPainted(false)
     , mSurfaceDifferenceRect(0,0,0,0)
 #if (MOZ_PLATFORM_MAEMO == 5) || (MOZ_PLATFORM_MAEMO == 6)
     , mMaemoImageRendering(PR_FALSE)
@@ -2472,7 +2473,8 @@ PluginInstanceChild::UpdateWindowAttributes(bool aForceSetWindow)
         WINDOWPOS winpos = {
             0, 0,
             mWindow.x, mWindow.y,
-            mWindow.width, mWindow.height
+            mWindow.width, mWindow.height,
+            0
         };
         NPEvent pluginEvent = {
             WM_WINDOWPOSCHANGED, 0,
@@ -2718,6 +2720,7 @@ PluginInstanceChild::ShowPluginFrame()
     } else {
         PaintRectToSurface(rect, mCurrentSurface, gfxRGBA(0.0, 0.0, 0.0, 0.0));
     }
+    mHasPainted = true;
 
     NPRect r = { (uint16_t)rect.y, (uint16_t)rect.x,
                  (uint16_t)rect.YMost(), (uint16_t)rect.XMost() };
@@ -2815,7 +2818,7 @@ PluginInstanceChild::InvalidateRectDelayed(void)
     }
 
     mCurrentInvalidateTask = nsnull;
-    if (mAccumulatedInvalidRect.IsEmpty() || !IsVisible()) {
+    if (mAccumulatedInvalidRect.IsEmpty() || (mHasPainted && !IsVisible())) {
         return;
     }
 
@@ -2827,7 +2830,7 @@ PluginInstanceChild::InvalidateRectDelayed(void)
 void
 PluginInstanceChild::AsyncShowPluginFrame(void)
 {
-    if (mCurrentInvalidateTask || !IsVisible()) {
+    if (mCurrentInvalidateTask || (mHasPainted && !IsVisible())) {
         return;
     }
 
diff --git a/dom/plugins/PluginInstanceChild.h b/dom/plugins/PluginInstanceChild.h
index 833bf1d87df3..bc3fb5654896 100644
--- a/dom/plugins/PluginInstanceChild.h
+++ b/dom/plugins/PluginInstanceChild.h
@@ -498,6 +498,11 @@ private:
     // supports NPPVpluginTransparentAlphaBool (which is not part of NPAPI yet)
     bool mDoAlphaExtraction;
 
+    // true when the plugin has painted at least once. We use this to ensure
+    // that we ask a plugin to paint at least once even if it's invisible;
+    // some plugin (instances) rely on this in order to work properly.
+    bool mHasPainted;
+
     // Cached rectangle rendered to previous surface(mBackSurface)
     // Used for reading back to current surface and syncing data,
     // in plugin coordinates.