Bug 573829, part 2: Add TextureImage API for getting backing ASurface (if exists) and determining whether it's in an update. sr=vlad

gfx/thebes/GLContext.h

@@ -187,8 +187,17 @@ public:
     GLuint Texture() { return mTexture; }
 
     /** Can be called safely at any time. */
+
+    /**
+     * If this TextureImage has a permanent gfxASurface backing,
+     * return it.  Otherwise return NULL.
+     */
+    virtual already_AddRefed<gfxASurface> GetBackingSurface()
+    { return NULL; }
+
     const nsIntSize& GetSize() const { return mSize; }
     ContentType GetContentType() const { return mContentType; }
+    virtual PRBool InUpdate() const = 0;
 
 protected:
     /**
@@ -226,6 +235,8 @@ public:
     virtual gfxContext* BeginUpdate(nsIntRegion& aRegion);
     virtual PRBool EndUpdate();
 
+    virtual PRBool InUpdate() const { return !!mUpdateContext; }
+
 protected:
     typedef gfxASurface::gfxImageFormat ImageFormat;
 

gfx/thebes/GLContextProviderEGL.cpp

@@ -736,6 +736,15 @@ public:
         return PR_FALSE;        // texture not bound
     }
 
+    virtual already_AddRefed<gfxASurface>
+    GetBackingSurface()
+    {
+        NS_ADDREF(mImpl->mThebesSurface);
+        return mImpl->mThebesSurface.get();
+    }
+
+    virtual PRBool InUpdate() const { return !!mUpdateContext; }
+
 private:
     GLContext* mGLContext;
     nsRefPtr<GLContextEGL> mImpl;