[v8] don't crash when ArrayBuffer allocation fails

third_party/WebKit/Source/bindings/core/v8/V8Initializer.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 314 matching lines @@
 
     isolate->SetAutorunMicrotasks(false);
 }
 
 namespace {
 
 class ArrayBufferAllocator : public v8::ArrayBuffer::Allocator {
     void* Allocate(size_t size) override
     {
         void* data;
-        WTF::ArrayBufferContents::allocateMemory(size, WTF::ArrayBufferContents::ZeroInitialize, data);
+        WTF::ArrayBufferContents::allocateMemoryOrNull(size, WTF::ArrayBufferContents::ZeroInitialize, data);

[haraken, 2016/01/14 01:52:33]

I'm a bit confused. If you call allocateMemoryOrNull and take no action when it
returns nullptr, you are just ignoring the allocation failure, aren't you?

[caitp (gmail), 2016/01/14 01:59:04]

The ArrayBufferAllocator is used (only) by v8, which throws a RangeError of
allocation fails (signaled by returning null here). The idea is to make the
Blink ArrayBufferAllocator honor the implicit contract that v8 expects

[haraken, 2016/01/14 02:17:31]

Thanks, makes sense. Can you add a comment about it?

         return data;
     }
 
     void* AllocateUninitialized(size_t size) override
     {
         void* data;
-        WTF::ArrayBufferContents::allocateMemory(size, WTF::ArrayBufferContents::DontInitialize, data);
+        WTF::ArrayBufferContents::allocateMemoryOrNull(size, WTF::ArrayBufferContents::DontInitialize, data);
         return data;
     }
 
     void Free(void* data, size_t size) override
     {
         WTF::ArrayBufferContents::freeMemory(data, size);
     }
 };
 
 } // namespace
@@ skipping 86 matching lines @@
 
     isolate->AddMessageListener(messageHandlerInWorker);
     isolate->SetFatalErrorHandler(reportFatalErrorInWorker);
 
     uint32_t here;
     isolate->SetStackLimit(reinterpret_cast<uintptr_t>(&here - kWorkerMaxStackSize / sizeof(uint32_t*)));
     isolate->SetPromiseRejectCallback(promiseRejectHandlerInWorker);
 }
 
 } // namespace blink