Add MemoryWedge to ios/.

ios/chrome/browser/memory/memory_wedge.h

Index: ios/chrome/browser/memory/memory_wedge.h
diff --git a/ios/chrome/browser/memory/memory_wedge.h b/ios/chrome/browser/memory/memory_wedge.h
new file mode 100644
index 0000000000000000000000000000000000000000..1df72446df80a17391ae77930a6d3eb29eb12bde
--- /dev/null
+++ b/ios/chrome/browser/memory/memory_wedge.h
@@ -0,0 +1,21 @@
+// Copyright 2015 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.
+
+#ifndef IOS_CHROME_BROWSER_MEMORY_MEMORY_WEDGE_H_
+#define IOS_CHROME_BROWSER_MEMORY_MEMORY_WEDGE_H_
+
+#include <stdlib.h>
+
+namespace memory_wedge {
+
+// Allocates a chunk of memory that will stay until termination.
+// If wedge_size_in_mb is 0, this is a no-op.
+void AddWedge(size_t wedge_size_in_mb);
+
+// For testing only.
+void RemoveWedgeForTesting();
+
+}  // namespace memory_wedge
+
+#endif  // IOS_CHROME_BROWSER_MEMORY_MEMORY_WEDGE_H_