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 a2c37c6e72f92de7ce16d301632dacdb6dbb1fbf..9c7507a4efc639a60b8e5a15c4621e9f5ec9bfe4 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"
 
@@ -223,6 +224,7 @@ 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) {
@@ -232,6 +234,12 @@ 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) {
+        SkBitmapCache::NotifyGenIDStale(fGenerationID);

[mtklein, 2015/01/07 21:52:43]

Feels weird knowing both these calls really grab and release the same mutex down
under the covers.  No suggested change here though... can't think of anything
that doesn't really slice through the API barriers.

[reed1, 2015/01/07 22:20:41]

Agree on both counts.

*if* we (later) standardize on a genID field, then this problem goes away

[reed1, 2015/02/18 17:30:32]

Captured this comment in a comment.

+        SkMipMapCache::NotifyGenIDStale(fGenerationID);
+    }
 }
 
 void SkPixelRef::notifyPixelsChanged() {