Notify resource caches when pixelref genID goes stale

src/core/SkPixelRef.cpp

Index: src/core/SkPixelRef.cpp
diff --git a/src/core/SkPixelRef.cpp b/src/core/SkPixelRef.cpp
index c73c2f4b7dc3db2487a4d18e19b972d50b0a970f..4e600da7b091c33daf6422d785eca44ae18abdd6 100644
--- a/src/core/SkPixelRef.cpp
+++ b/src/core/SkPixelRef.cpp
@@ -5,6 +5,7 @@
  * found in the LICENSE file.
  */
 
+#include "SkBitmapCache.h"
 #include "SkPixelRef.h"
 #include "SkThread.h"
 
@@ -214,6 +215,7 @@ void SkPixelRef::addGenIDChangeListener(GenIDChangeListener* listener) {
     *fGenIDChangeListeners.append() = listener;
 }
 
+// we need to be called *before* the genID gets changed or zerod
 void SkPixelRef::callGenIDChangeListeners() {
     // We don't invalidate ourselves if we think another SkPixelRef is sharing our genID.
     if (fUniqueGenerationID) {
@@ -223,6 +225,11 @@ void SkPixelRef::callGenIDChangeListeners() {
     }
     // Listeners get at most one shot, so whether these triggered or not, blow them away.
     fGenIDChangeListeners.deleteAll();
+
+    // if fGenerationID is 0, then perhaps we never had one, and we are in the destructor
+    if (fGenerationID) {
+        SkNotifyBitmapGenIDIsStale(fGenerationID);

[mtklein, 2015/02/24 16:43:39]

Just noticed.... this should probably go inside the if (fUniqueGenerationID) {
}, which implies and is stronger than an non-zero fGenerationID.  It's safe to
invalidate the gen ID where you're doing it (it's safe to do it anywhere), but
you may end up purging resources too early unless you're guarded by
fUniqueGenerationID.

[reed2, 2015/02/24 17:44:52]

Ah, thanks. I didn't really know what fUniqueGenerationID meant...

+    }
 }
 
 void SkPixelRef::notifyPixelsChanged() {