Revert temporary device independent bitmap

Manual revert of crrev.com/10069004, which shouldn't be necessary
given changes in the rendering pipeline over the last four and a
half years.

R=bbudge@chromium.org
BUG=543755

Review-Url: https://codereview.chromium.org/2361903004
Cr-Commit-Position: refs/heads/master@{#420659}

content/renderer/pepper/pepper_graphics_2d_host.cc

@@ -354,14 +354,6 @@ void PepperGraphics2DHost::Paint(blink::WebCanvas* canvas,
     canvas->drawRect(sk_invalidate_rect, paint);
   }
 
-  SkBitmap image;
-  // Copy to device independent bitmap when target canvas doesn't support
-  // platform paint.
-  if (!skia::SupportsPlatformPaint(canvas))
-    backing_bitmap.copyTo(&image, kN32_SkColorType);
-  else
-    image = backing_bitmap;
-
   SkPaint paint;
   if (is_always_opaque_) {
     // When we know the device is opaque, we can disable blending for slightly
@@ -374,7 +366,8 @@ void PepperGraphics2DHost::Paint(blink::WebCanvas* canvas,
     canvas->scale(scale_, scale_);
     pixel_origin.scale(1.0f / scale_);
   }
-  canvas->drawBitmap(image, pixel_origin.x(), pixel_origin.y(), &paint);
+  canvas->drawBitmap(backing_bitmap, pixel_origin.x(), pixel_origin.y(),
+                     &paint);
 }
 
 void PepperGraphics2DHost::ViewInitiatedPaint() {