Purge cached resources on SkImage destruction.

src/image/SkImage.cpp

Index: src/image/SkImage.cpp
diff --git a/src/image/SkImage.cpp b/src/image/SkImage.cpp
index 654b848fce22073ba274c57cbe0768c3464093dc..eef9f08d05ef1a24392d9df7c3838a3202121fd9 100644
--- a/src/image/SkImage.cpp
+++ b/src/image/SkImage.cpp
@@ -6,6 +6,7 @@
  */
 
 #include "SkBitmap.h"
+#include "SkBitmapCache.h"
 #include "SkCanvas.h"
 #include "SkData.h"
 #include "SkImageGenerator.h"
@@ -33,6 +34,8 @@ SkImage::SkImage(int width, int height, uint32_t uniqueID)
     SkASSERT(height > 0);
 }
 
+SkImage::~SkImage() { }

[reed1, 2015/09/18 14:32:53]

nit: I think we can put this impl ( {} ) in the header.

[f(malita), 2015/09/18 15:00:40]

Dropped the SkImage dtor completely.

+
 const void* SkImage::peekPixels(SkImageInfo* info, size_t* rowBytes) const {
     SkImageInfo infoStorage;
     size_t rowBytesStorage;
@@ -210,6 +213,23 @@ static bool raster_canvas_supports(const SkImageInfo& info) {
     return false;
 }
 
+static SkSurfaceProps copy_or_safe_defaults(const SkSurfaceProps* props) {
+    return props ? *props : SkSurfaceProps(0, kUnknown_SkPixelGeometry);

[mtklein, 2015/09/18 14:32:36]

We might even think about adding SkSurfaceProps::SafeDefaults().  I was just
puzzling through this the other day.

+}
+
+SkImage_Base::SkImage_Base(int width, int height, uint32_t uniqueID, const SkSurfaceProps* props)
+    : INHERITED(width, height, uniqueID)
+    , fProps(copy_or_safe_defaults(props))

[mtklein, 2015/09/18 14:32:36]

You ought to be able to do fAddedToCache(false) here.  It'll be a bit faster,
but probably nothing life-changing.  That'd start it off initialized rather than
start it uninitialized then atomically initialize it.  (There's rarely a need to
do anything atomic in constructors.)

[f(malita), 2015/09/18 15:00:40]

Thanks, done.

+{
+    fAddedToCache.store(false);
+}
+
+SkImage_Base::~SkImage_Base() {
+    if (fAddedToCache.load()) {
+        SkNotifyBitmapGenIDIsStale(this->uniqueID());

[mtklein, 2015/09/18 14:32:36]

Are bitmap genids and skimage genids in the same namespace?

[f(malita), 2015/09/18 15:00:40]

Yes.

+    }
+}
+
 bool SkImage_Base::onReadPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes,
                                 int srcX, int srcY) const {
     if (!raster_canvas_supports(dstInfo)) {