hide virtuals on device for width/height/isopaque

include/gpu/SkGpuDevice.h

Index: include/gpu/SkGpuDevice.h
diff --git a/include/gpu/SkGpuDevice.h b/include/gpu/SkGpuDevice.h
index b4234e84d21111802fedcb2229df5160ffbb7823..0b6bbc18570680584129f3fe086492beb86bc8dd 100644
--- a/include/gpu/SkGpuDevice.h
+++ b/include/gpu/SkGpuDevice.h
@@ -71,16 +71,8 @@ public:
 
     virtual GrRenderTarget* accessRenderTarget() SK_OVERRIDE;
 
-    // overrides from SkBaseDevice
-    virtual int width() const SK_OVERRIDE {
-        return NULL == fRenderTarget ? 0 : fRenderTarget->width();
-    }
-    virtual int height() const SK_OVERRIDE {
-        return NULL == fRenderTarget ? 0 : fRenderTarget->height();
-    }
-    virtual bool isOpaque() const SK_OVERRIDE {
-        return NULL == fRenderTarget ? false
-                                     : kRGB_565_GrPixelConfig == fRenderTarget->config();
+    virtual SkImageInfo imageInfo() const SK_OVERRIDE {
+        return fRenderTarget ? fRenderTarget->info() : SkImageInfo::MakeUnknown();
     }
 
     virtual void clear(SkColor color) SK_OVERRIDE;