Don't use SetAnimatedThemeCursor() at interrupt time. Doh! Instead just back down to using the normal watch cursor. Not as pretty, but doesn't wipe out the machine at random. r=pchen/a=sfraser, bug#52565.

gfx/src/mac/nsWatchTask.cpp

@@ -68,6 +68,12 @@ nsWatchTask :: ~nsWatchTask ( )
 void
 nsWatchTask :: Start ( )
 {
+  // get the watch cursor and lock it high
+  CursHandle watch = ::GetCursor ( watchCursor );
+  if ( !watch )
+    return;
+  mWatchCursor = **watch;
+  
   // setup the task
   mTask.qType = vType;
 	mTask.vblAddr = NewVBLProc((VBLProcPtr)DoWatchTask);
@@ -98,12 +104,12 @@ nsWatchTask :: DoWatchTask ( nsWatchTask* inSelf )
     if ( !inSelf->mSuspended  ) {
       if ( !inSelf->mBusy && !LMGetCrsrBusy() ) {
         if ( ::TickCount() - inSelf->mTicks > kTicksToShowWatch ) {
-          ::SetAnimatedThemeCursor(kThemeWatchCursor, inSelf->mAnimation);
+          ::SetCursor ( &(inSelf->mWatchCursor) );
           inSelf->mBusy = PR_TRUE;
         }
       }
       else
-        ::SetAnimatedThemeCursor(kThemeWatchCursor, inSelf->mAnimation);
+        ::SetCursor ( &(inSelf->mWatchCursor) );
       
       // next frame in cursor animation    
       ++inSelf->mAnimation;

gfx/src/mac/nsWatchTask.h

@@ -26,6 +26,7 @@
 
 
 #include <Retrace.h>
+#include <Quickdraw.h>
 #include "PRTypes.h"
 #include "nscore.h"
 
@@ -74,6 +75,7 @@ private:
   long mChecksum;           // 'mozz' to validate we have real data at interrupt time (not needed?)
   void* mSelf;              // so we can get back to |this| from the static routine
   long mTicks;              // last time the event loop was hit
+  Cursor mWatchCursor;      // the watch cursor
   PRPackedBool mBusy;       // are we currently spinning the cursor?
   PRPackedBool mSuspended;  // set if we've temporarily suspended operation
   PRPackedBool mInstallSucceeded;     // did we succeed in installing the task? (used in dtor)