Index: layout/base/nsPresContext.cpp
===================================================================
RCS file: /cvsroot/mozilla/layout/base/nsPresContext.cpp,v
retrieving revision 3.288.12.2.4.1
diff -d -u -p -r3.288.12.2.4.1 nsPresContext.cpp
--- layout/base/nsPresContext.cpp	21 Apr 2006 23:30:50 -0000	3.288.12.2.4.1
+++ layout/base/nsPresContext.cpp	26 Sep 2006 19:26:40 -0000
@@ -73,6 +73,9 @@
 #include "nsIDOMDocument.h"
 #include "nsAutoPtr.h"
 #include "nsEventStateManager.h"
+#include "nsIEventQueue.h"
+#include "nsIEventQueueService.h"
+
 #ifdef IBMBIDI
 #include "nsBidiPresUtils.h"
 #endif // IBMBIDI
@@ -267,6 +270,7 @@ nsPresContext::~nsPresContext()
   NS_IF_RELEASE(mDeviceContext);
   NS_IF_RELEASE(mLookAndFeel);
   NS_IF_RELEASE(mLangGroup);
+  NS_IF_RELEASE(mEventQueueService);
 }
 
 NS_IMPL_ISUPPORTS2(nsPresContext, nsPresContext, nsIObserver)
@@ -285,6 +289,17 @@ static const char* const kGenericFont[] 
   ".fantasy."
 };
 
+// Set to true when LookAndFeelChanged needs to be called.  This is used
+// because the look and feel is a service, so there's no need to notify it from
+// more than one prescontext.
+static PRBool sLookAndFeelChanged;
+
+// Set to true when ThemeChanged needs to be called on mTheme.  This is used
+// because mTheme is a service, so there's no need to notify it from more than
+// one prescontext.
+static PRBool sThemeChanged;
+
+
 void
 nsPresContext::GetFontPreferences()
 {
@@ -709,6 +724,9 @@ nsPresContext::Init(nsIDeviceContext* aD
                                        this);
 #endif
 
+  rv = CallGetService(NS_EVENTQUEUESERVICE_CONTRACTID, &mEventQueueService);
+  NS_ENSURE_SUCCESS(rv, rv);
+
   // Initialize our state from the user preferences
   GetUserPreferences();
 
@@ -1180,33 +1198,126 @@ nsPresContext::GetTheme()
 void
 nsPresContext::ThemeChanged()
 {
+  if (!mPendingThemeChanged) {
+    sLookAndFeelChanged = PR_TRUE;
+    sThemeChanged = PR_TRUE;
+
+    nsCOMPtr<nsIEventQueue> eventQ;
+    mEventQueueService->
+      GetSpecialEventQueue(nsIEventQueueService::UI_THREAD_EVENT_QUEUE,
+                           getter_AddRefs(eventQ));
+    if (!eventQ) {
+      return;
+    }
+
+    PLEvent* evt = new PLEvent();
+    if (!evt) {
+      return;
+    }
+
+    PL_InitEvent(evt, this, nsPresContext::ThemeChangedInternal,
+                 nsPresContext::DestroyThemeChangeEvt);
+
+    // After this point, event destruction will release |this|
+    NS_ADDREF_THIS();
+
+    nsresult rv = eventQ->PostEvent(evt);
+    if (NS_FAILED(rv)) {
+      PL_DestroyEvent(evt);
+    } else {
+      mPendingThemeChanged = PR_TRUE;
+    }
+  }    
+}
+
+void* PR_CALLBACK
+nsPresContext::ThemeChangedInternal(PLEvent *aEvent)
+{
+  nsPresContext* pc = NS_STATIC_CAST(nsPresContext*, aEvent->owner);
+
+  pc->mPendingThemeChanged = PR_FALSE;
+
   // Tell the theme that it changed, so it can flush any handles to stale theme
   // data.
-  if (mTheme)
-    mTheme->ThemeChanged();
+  if (pc->mTheme && sThemeChanged) {
+    pc->mTheme->ThemeChanged();
+    sThemeChanged = PR_FALSE;
+  }
 
   // Clear all cached nsILookAndFeel colors.
-  if (mLookAndFeel)
-    mLookAndFeel->LookAndFeelChanged();
+  if (pc->mLookAndFeel && sLookAndFeelChanged) {
+    pc->mLookAndFeel->LookAndFeelChanged();
+    sLookAndFeelChanged = PR_FALSE;
+  }
 
   // We have to clear style data because the assumption of style rule
   // immutability has been violated since any style rule that uses
   // system colors or fonts (and probably -moz-appearance as well) has
   // changed.
-  nsPresContext::ClearStyleDataAndReflow();
+  pc->ClearStyleDataAndReflow();
+
+  return nsnull;
+}
+
+
+void PR_CALLBACK
+nsPresContext::DestroyThemeChangeEvt(PLEvent* aEvent)
+{
+  nsPresContext* pc = NS_STATIC_CAST(nsPresContext*, aEvent->owner);
+  NS_RELEASE(pc);
+  delete aEvent;
 }
 
 void
 nsPresContext::SysColorChanged()
 {
-  if (mLookAndFeel) {
+  if (!mPendingSysColorChanged) {
+    sLookAndFeelChanged = PR_TRUE;
+
+    nsCOMPtr<nsIEventQueue> eventQ;
+    mEventQueueService->
+      GetSpecialEventQueue(nsIEventQueueService::UI_THREAD_EVENT_QUEUE,
+                           getter_AddRefs(eventQ));
+    if (!eventQ) {
+      return;
+    }
+
+    PLEvent* evt = new PLEvent();
+    if (!evt) {
+      return;
+    }
+
+    PL_InitEvent(evt, this, nsPresContext::SysColorChangedInternal,
+                 nsPresContext::DestroySysColorChangeEvt);
+
+    // After this point, event destruction will release |this|
+    NS_ADDREF_THIS();
+
+    nsresult rv = eventQ->PostEvent(evt);
+    if (NS_FAILED(rv)) {
+      PL_DestroyEvent(evt);
+    } else {
+      mPendingSysColorChanged = PR_TRUE;
+    }
+  }
+}
+
+void* PR_CALLBACK
+nsPresContext::SysColorChangedInternal(PLEvent *aEvent)
+{
+  nsPresContext* pc = NS_STATIC_CAST(nsPresContext*, aEvent->owner);
+
+  pc->mPendingSysColorChanged = PR_FALSE;
+  
+  if (pc->mLookAndFeel && sLookAndFeelChanged) {
      // Don't use the cached values for the system colors
-    mLookAndFeel->LookAndFeelChanged();
+    pc->mLookAndFeel->LookAndFeelChanged();
+    sLookAndFeelChanged = PR_FALSE;
   }
-   
+
   // Reset default background and foreground colors for the document since
   // they may be using system colors
-  GetDocumentColorPreferences();
+  pc->GetDocumentColorPreferences();
 
   // Clear out all of the style data since it may contain RGB values
   // which originated from system colors.
@@ -1222,7 +1333,17 @@ nsPresContext::SysColorChanged()
   // data without reflowing/updating views will lead to incorrect change hints
   // later, because when generating change hints, any style structs which have
   // been cleared and not reread are assumed to not be used at all.
-  ClearStyleDataAndReflow();
+  pc->ClearStyleDataAndReflow();
+
+  return nsnull;
+}
+
+void PR_CALLBACK
+nsPresContext::DestroySysColorChangeEvt(PLEvent* aEvent)
+{
+  nsPresContext* pc = NS_STATIC_CAST(nsPresContext*, aEvent->owner);
+  NS_RELEASE(pc);
+  delete aEvent;
 }
 
 void
Index: layout/base/nsPresContext.h
===================================================================
RCS file: /cvsroot/mozilla/layout/base/nsPresContext.h,v
retrieving revision 3.150.4.2
diff -d -u -p -r3.150.4.2 nsPresContext.h
--- layout/base/nsPresContext.h	29 Aug 2005 16:15:39 -0000	3.150.4.2
+++ layout/base/nsPresContext.h	26 Sep 2006 19:26:40 -0000
@@ -56,6 +56,7 @@
 #include "nsCRT.h"
 #include "nsIPrintSettings.h"
 #include "nsPropertyTable.h"
+#include "plevent.h"
 #ifdef IBMBIDI
 class nsBidiPresUtils;
 #endif // IBMBIDI
@@ -76,6 +77,7 @@ class nsIAtom;
 class nsIEventStateManager;
 class nsIURI;
 class nsILookAndFeel;
+class nsIEventQueueService;
 class nsICSSPseudoComparator;
 class nsIAtom;
 struct nsStyleStruct;
@@ -627,6 +629,14 @@ public:
   const nscoord* GetBorderWidthTable() { return mBorderWidthTable; }
 
 protected:
+  static NS_HIDDEN_(void*) PR_CALLBACK ThemeChangedInternal(PLEvent* aEvent);
+  static NS_HIDDEN_(void*) PR_CALLBACK SysColorChangedInternal(PLEvent* aEvent);
+  static NS_HIDDEN_(void) PR_CALLBACK DestroyThemeChangeEvt(PLEvent* aEvent);
+  static NS_HIDDEN_(void) PR_CALLBACK DestroySysColorChangeEvt(PLEvent* aEvent);
+
+  friend void* PR_CALLBACK ThemeChangedInternal(PLEvent* aEvent);
+  friend void* PR_CALLBACK SysColorChangedInternal(PLEvent* aEvent);
+
   NS_HIDDEN_(void) SetImgAnimations(nsIContent *aParent, PRUint16 aMode);
   NS_HIDDEN_(void) GetDocumentColorPreferences();
 
@@ -654,6 +664,7 @@ protected:
                                         // from gfx back to layout.
   nsIEventStateManager* mEventManager;  // [STRONG]
   nsILookAndFeel*       mLookAndFeel;   // [STRONG]
+  nsIEventQueueService *mEventQueueService; // [STRONG]
   nsIAtom*              mMedium;        // initialized by subclass ctors;
                                         // weak pointer to static atom
 
@@ -724,6 +735,8 @@ protected:
   unsigned              mCanPaginatedScroll : 1;
   unsigned              mDoScaledTwips : 1;
   unsigned              mEnableJapaneseTransform : 1;
+  unsigned              mPendingSysColorChanged : 1;
+  unsigned              mPendingThemeChanged : 1;
 #ifdef IBMBIDI
   unsigned              mIsVisual : 1;
   unsigned              mIsBidiSystem : 1;