Enable skia asserts. They were disabled some time ago due to...

skia/config/SkUserConfig.h

 /*
  * Copyright (C) 2006 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
@@ skipping 185 matching lines @@
 #define SK_G32_SHIFT 8
 #define SK_B32_SHIFT 0
 
 #endif
 
 // The default crash macro writes to badbeef which can cause some strange
 // problems. Instead, pipe this through to the logging function as a fatal
 // assertion.
 #define SK_CRASH() SkDebugf_FileLine(__FILE__, __LINE__, true, "SK_CRASH")
 
-// TODO(brettw) bug 6373: Re-enable Skia assertions. This is blocked on fixing
-// some of our transparency handling which generates purposely-invalid colors,
-// in turn causing assertions.
-//#ifndef NDEBUG
-//  #define SK_DEBUG
-//  #undef SK_RELEASE
-  #undef SK_SUPPORT_UNITTEST  // This is only necessary in debug mode since
-                              // we've disabled assertions. When we re-enable
-                              // them, this line can be removed.
-//#else
-  #define SK_RELEASE
-  #undef SK_DEBUG
-//#endif
-
 // For now (and to avoid rebaselining 1700+ tests), we'll use the old version
 // of SkAlpha255To256.
 #define SK_USE_OLD_255_TO_256
 
 // ===== End Chrome-specific definitions =====
 
 #endif