make allocPixels throw on failure

src/images/SkImageDecoder_libjpeg.cpp

 /*
  * Copyright 2007 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 "SkImageDecoder.h"
 #include "SkImageEncoder.h"
@@ skipping 834 matching lines @@
     int h = rect.height() / actualSampleSize;
     bool swapOnly = (rect == region) && bm->isNull() &&
                     (w == bitmap.width()) && (h == bitmap.height()) &&
                     ((startX - rect.x()) / actualSampleSize == 0) &&
                     ((startY - rect.y()) / actualSampleSize == 0);
     if (swapOnly) {
         if (!this->allocPixelRef(&bitmap, NULL)) {
             return return_false(*cinfo, bitmap, "allocPixelRef");
         }
     } else {
-        if (!bitmap.allocPixels()) {
+        if (!bitmap.tryAllocPixels()) {
             return return_false(*cinfo, bitmap, "allocPixels");
         }
     }
 
     SkAutoLockPixels alp(bitmap);
 
 #ifdef ANDROID_RGB
     /* short-circuit the SkScaledBitmapSampler when possible, as this gives
        a significant performance boost.
     */
@@ skipping 367 matching lines @@
     return SkImageDecoder::kUnknown_Format;
 }
 
 static SkImageEncoder* sk_libjpeg_efactory(SkImageEncoder::Type t) {
     return (SkImageEncoder::kJPEG_Type == t) ? SkNEW(SkJPEGImageEncoder) : NULL;
 }
 
 static SkImageDecoder_DecodeReg gDReg(sk_libjpeg_dfactory);
 static SkImageDecoder_FormatReg gFormatReg(get_format_jpeg);
 static SkImageEncoder_EncodeReg gEReg(sk_libjpeg_efactory);