Fixed bug with SkImage leaving canvas backing store in an immutable state after destroy.

tests/SurfaceTest.cpp

Index: tests/SurfaceTest.cpp
===================================================================
--- tests/SurfaceTest.cpp	(revision 8437)
+++ tests/SurfaceTest.cpp	(working copy)
@@ -133,15 +133,32 @@
         testPaint))
 }
 
+static void TestSurfaceWritableAfterSnapshotRelease(skiatest::Reporter* reporter,
+                                                    SurfaceType surfaceType,
+                                                    GrContext* context) {
+    // This test succeeds by not triggering an assertion.
+    // The test verifies that the surface remains writable (usable) after
+    // acquiring and releasing a snapshot without triggering a copy on write.
+    SkSurface* surface = createSurface(surfaceType, context);
+    SkAutoTUnref<SkSurface> aur_surface(surface);
+    SkCanvas* canvas = surface->getCanvas();
+    canvas->clear(1);
+    surface->newImageShapshot()->unref();  // Create and destroy SkImage
+    canvas->clear(2);
+}
+
 static void TestSurface(skiatest::Reporter* reporter) {

[bsalomon, 2013/04/03 14:13:43]

Just noting that TestSurface and TestSurfaceGpu could be combined as:

GrContext* context = factory->get(GrContextFactory::kNative_GLContextType);
TestSurfaceCopyOnWrite(reporter, kRaster_SurfaceType, NULL);
TestSurfaceCopyOnWrite(reporter, kPicture_SurfaceType, NULL);
TestSurfaceCopyOnWrite(reporter, kPicture_SurfaceType, NULL);
TestSurfaceCopyOnWrite(reporter, kGpu_SurfaceType, context);
TestSurfaceWritableAfterSnapshotRelease(reporter, kRaster_SurfaceType, NULL);
TestSurfaceWritableAfterSnapshotRelease(reporter, kPicture_SurfaceType, NULL);
TestSurfaceWritableAfterSnapshotRelease(reporter, kGpu_SurfaceType, context);

     TestSurfaceCopyOnWrite(reporter, kRaster_SurfaceType, NULL);
     TestSurfaceCopyOnWrite(reporter, kPicture_SurfaceType, NULL);
+    TestSurfaceWritableAfterSnapshotRelease(reporter, kRaster_SurfaceType, NULL);
+    TestSurfaceWritableAfterSnapshotRelease(reporter, kPicture_SurfaceType, NULL);
 }
 
 static void TestSurfaceGpu(skiatest::Reporter* reporter, GrContextFactory* factory) {
 #if SK_SUPPORT_GPU
     GrContext* context = factory->get(GrContextFactory::kNative_GLContextType);
     TestSurfaceCopyOnWrite(reporter, kGpu_SurfaceType, context);
+    TestSurfaceWritableAfterSnapshotRelease(reporter, kGpu_SurfaceType, context);
 #endif
 }