Hookup the generic heap intercept for Windows.

base/allocator/allocator_shim_default_dispatch_to_winheap.cc

Index: base/allocator/allocator_shim_default_dispatch_to_winheap.cc
diff --git a/base/allocator/allocator_shim_default_dispatch_to_winheap.cc b/base/allocator/allocator_shim_default_dispatch_to_winheap.cc
new file mode 100644
index 0000000000000000000000000000000000000000..fec64c121cfc544a35cbf56180830a26fa2169ad
--- /dev/null
+++ b/base/allocator/allocator_shim_default_dispatch_to_winheap.cc
@@ -0,0 +1,48 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "base/allocator/allocator_shim.h"
+
+#include "base/allocator/allocator_impl_win.h"
+#include "base/logging.h"
+
+namespace {
+
+using base::allocator::AllocatorDispatch;
+
+void* WinHeapMalloc(const AllocatorDispatch*, size_t size) {

[Primiano Tucci (use gerrit), 2016/07/12 14:51:05]

Can you add some prefix to these functions (DoWinHeap? CallWinHeap?
DunnoWinHeap) just so they don't clash with the one in the other file? I know
this is a different namespace, but in case they show up in crashes will make the
code easier to codesearch. namespaces can be still a bit confusing for humans.

[Sigurður Ásgeirsson, 2016/07/14 19:04:27]

Yeah, naming - I went apeshit with prefix and suffix. Hopefully good enough?

+  return base::allocator::WinHeapMalloc(size);
+}
+
+void* WinHeapCalloc(const AllocatorDispatch* self, size_t n, size_t elem_size) {
+  return base::allocator::WinHeapCalloc(n, elem_size);
+}
+
+void* WinHeapMemalign(const AllocatorDispatch* self,
+                      size_t alignment,
+                      size_t size) {
+  NOTREACHED() << "The windows heap does not support memalign.";

[Primiano Tucci (use gerrit), 2016/07/12 14:51:05]

I'd make this a CHECK(false), so shows up in production crashes if we do
something silly in allocator_shim.cc
IIRC NOTREACHED is a noop when building in release (% DCHECK_ALWAYS_ON)

[Sigurður Ásgeirsson, 2016/07/14 19:04:27]

Done.

+  return nullptr;
+}
+
+void* WinHeapRealloc(const AllocatorDispatch* self,
+                     void* address,
+                     size_t size) {
+  return base::allocator::WinHeapRealloc(address, size);
+}
+
+void WinHeapFree(const AllocatorDispatch*, void* address) {
+  base::allocator::WinHeapFree(address);
+}
+
+}  // namespace
+
+const AllocatorDispatch AllocatorDispatch::default_dispatch = {
+    &WinHeapMalloc,
+    &WinHeapCalloc,
+    &WinHeapMemalign,
+    &WinHeapRealloc,
+    &WinHeapFree,
+    nullptr, /* next */
+};