Change some more GMs to clear to opaque black, not transparent black.

gm/displacement.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmapSource.h"
 #include "SkDisplacementMapEffect.h"
 #include "gm.h"
@@ skipping 50 matching lines @@
         canvas->clipRect(SkRect::MakeWH(SkIntToScalar(fBitmap.width()), SkIntToScalar(fBitmap.height())));
         canvas->drawBitmap(fBitmap, 0, 0, &paint);
         canvas->restore();
     }
 
     virtual void onDraw(SkCanvas* canvas) {
         if (!fInitialized) {
             make_bitmaps();
             fInitialized = true;
         }
-        canvas->clear(0x00000000);
+        canvas->clear(SK_ColorBLACK);
         SkPaint paint;
         SkAutoTUnref<SkImageFilter> displ(SkBitmapSource::Create(fCheckerboard));
         paint.setImageFilter(SkDisplacementMapEffect::Create(
             SkDisplacementMapEffect::kR_ChannelSelectorType,
             SkDisplacementMapEffect::kG_ChannelSelectorType, 0.0f, displ))->unref();
         drawClippedBitmap(canvas, 0, 0, paint);
         paint.setImageFilter(SkDisplacementMapEffect::Create(
             SkDisplacementMapEffect::kB_ChannelSelectorType,
             SkDisplacementMapEffect::kA_ChannelSelectorType, 16.0f, displ))->unref();
         drawClippedBitmap(canvas, 100, 0, paint);
@@ skipping 125 matching lines @@
     SkBitmap fBitmap, fCheckerboard, fSmall, fLarge, fLargeW, fLargeH;
     bool fInitialized;
 };
 
 //////////////////////////////////////////////////////////////////////////////
 
 static GM* MyFactory(void*) { return new DisplacementMapGM; }
 static GMRegistry reg(MyFactory);
 
 }