Fix for bug 36849: Script animation that changes location and clip simultaneously no longer will flicker.

Checking in (for Robert O'Callahan) a change to the event priorities: reverting to standard priorities.
This was tested for weeks by several individuals with no bad effects reported. b=36849 r=attinasi

webshell/tests/viewer/nsWinMain.cpp

@@ -63,11 +63,10 @@ nsNativeViewerApp::Run()
 
   // Pump all messages
   do {
-    // Give priority to system messages (in particular keyboard, mouse,
+    // DO NOT Give priority to system messages (in particular keyboard, mouse,
     // timer, and paint messages).
     // Note: on Win98 and NT 5.0 we can also use PM_QS_INPUT and PM_QS_PAINT flags.
-    if (::PeekMessage(&msg, NULL, 0, WM_USER-1, PM_REMOVE) || 
-      ::PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
+    if (::PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
 
       keepGoing = (msg.message != WM_QUIT);
 

widget/src/windows/nsAppShell.cpp

@@ -88,12 +88,9 @@ NS_METHOD nsAppShell::Run(void)
 
   // Process messages
   do {
-    // Give priority to system messages (in particular keyboard, mouse,
+    // DO NOT Give priority to system messages (in particular keyboard, mouse,
     // timer, and paint messages).
-    if (::PeekMessage(&msg, NULL, WM_KEYFIRST, WM_KEYLAST, PM_REMOVE) ||
-        ::PeekMessage(&msg, NULL, WM_MOUSEFIRST, WM_MOUSELAST, PM_REMOVE) || 
-        ::PeekMessage(&msg, NULL, 0, WM_USER-1, PM_REMOVE) || 
-        ::PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
+    if (::PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
 
       keepGoing = (msg.message != WM_QUIT);