make allocPixels throw on failure

src/effects/SkMagnifierImageFilter.cpp

 /*
  * Copyright 2012 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkMagnifierImageFilter.h"
 #include "SkColorPriv.h"
@@ skipping 303 matching lines @@
         (fSrcRect.height() >= src.height())) {
       return false;
     }
 
     SkAutoLockPixels alp(src);
     SkASSERT(src.getPixels());
     if (!src.getPixels() || src.width() <= 0 || src.height() <= 0) {
       return false;
     }
 
-    if (!dst->allocPixels(src.info())) {
+    if (!dst->tryAllocPixels(src.info())) {
         return false;
     }
 
     SkScalar inv_inset = fInset > 0 ? SkScalarInvert(fInset) : SK_Scalar1;
 
     SkScalar inv_x_zoom = fSrcRect.width() / src.width();
     SkScalar inv_y_zoom = fSrcRect.height() / src.height();
 
     SkColor* sptr = src.getAddr32(0, 0);
     SkColor* dptr = dst->getAddr32(0, 0);
@@ skipping 29 matching lines @@
 
             int x_val = SkPin32(SkScalarFloorToInt(x_interp), 0, width - 1);
             int y_val = SkPin32(SkScalarFloorToInt(y_interp), 0, height - 1);
 
             *dptr = sptr[y_val * width + x_val];
             dptr++;
         }
     }
     return true;
 }