Some assert fixes for running the Fuzzer sample in GPU mode.

src/gpu/GrBlurUtils.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrBlurUtils.h"
 #include "GrDrawContext.h"
 #include "GrCaps.h"
@@ skipping 138 matching lines @@
                                        bool pathIsMutable) {
     SkASSERT(maskFilter);
 
     SkIRect clipBounds;
     clip.getConservativeBounds(drawContext->width(), drawContext->height(), &clipBounds);
     SkTLazy<SkPath> tmpPath;
     SkStrokeRec::InitStyle fillOrHairline;
 
     // We just fully apply the style here.
     if (style.applies()) {
-        if (!style.applyToPath(tmpPath.init(), &fillOrHairline, *path,
-                                   GrStyle::MatrixToScaleFactor(viewMatrix))) {
+        SkScalar scale = GrStyle::MatrixToScaleFactor(viewMatrix);
+        if (0 == scale || !style.applyToPath(tmpPath.init(), &fillOrHairline, *path, scale)) {
             return;
         }
         pathIsMutable = true;
         path = tmpPath.get();
     } else if (style.isSimpleHairline()) {
         fillOrHairline = SkStrokeRec::kHairline_InitStyle;
     } else {
         SkASSERT(style.isSimpleFill());
         fillOrHairline = SkStrokeRec::kFill_InitStyle;
     }
@@ skipping 122 matching lines @@
     }
 
     if (paint.getMaskFilter()) {
         draw_path_with_mask_filter(context, drawContext, clip, &grPaint, viewMatrix,
                                    paint.getMaskFilter(), style,
                                    path, pathIsMutable);
     } else {
         drawContext->drawPath(clip, grPaint, viewMatrix, *path, style);
     }
 }