[tracing] Add SkResourceCache statistics to chrome://tracing (chrome side)

skia/ext/SkTraceMemoryDump_chrome.h

+// 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 SKIA_EXT_SK_TRACE_MEMORY_DUMP_CHROME_H_
+#define SKIA_EXT_SK_TRACE_MEMORY_DUMP_CHROME_H_
+
+#include "third_party/skia/include/core/SkTraceMemoryDump.h"

[ericrk, 2015/08/25 20:14:50]

nit: Combine / alphabetize includes here?

+
+#include "base/macros.h"
+
+namespace base {
+namespace trace_event {
+class ProcessMemoryDump;
+}
+}
+
+namespace skia {

[ericrk, 2015/08/25 20:14:50]

SkDiscardableMemory_Chrome isn't in a skia namespace, but this is, why the
distinction? Not a big deal, just want to make sure we follow the existing
pattern if there is one.

[ssid, 2015/08/25 20:43:54]

um, I am not really sure, there are other files which use skia namespace, in
skia/ext. Just thought it is better to have namespace anyway.

[ericrk, 2015/08/25 20:49:56]

Ok, that's fine. Let's leave this as-is. I prefer the namespace.

+
+class SkTraceMemoryDump_Chrome : public SkTraceMemoryDump {
+ public:
+  SkTraceMemoryDump_Chrome(
+      base::trace_event::ProcessMemoryDump* process_memory_dump);
+  ~SkTraceMemoryDump_Chrome() override;
+
+  // SkTraceMemoryDump implementation:
+  void dumpNumericValue(const char* dumpName,
+                        const char* valueName,
+                        const char* units,
+                        uint64_t value) override;
+  void setMemoryBacking(const char* dumpName,
+                        const char* backingType,
+                        const char* backingObjectId) override;
+  void setDiscardableMemoryBacking(
+      const char* dumpName,
+      const SkDiscardableMemory& discardableMemoryObject) override;
+
+ private:
+  base::trace_event::ProcessMemoryDump* process_memory_dump_;
+
+  DISALLOW_COPY_AND_ASSIGN(SkTraceMemoryDump_Chrome);
+};
+
+}  // namespace skia
+
+#endif  // SKIA_EXT_SK_TRACE_MEMORY_DUMP_CHROME_H_