Add Web Resources usage to chrome://tracing.

third_party/WebKit/Source/platform/SharedBuffer.h

Index: third_party/WebKit/Source/platform/SharedBuffer.h
diff --git a/third_party/WebKit/Source/platform/SharedBuffer.h b/third_party/WebKit/Source/platform/SharedBuffer.h
index 94a6946a345cf9d1a370bb68cea9f438cb8bc9f0..56afb23204585ae47778f18f5487aaec9ad911a6 100644
--- a/third_party/WebKit/Source/platform/SharedBuffer.h
+++ b/third_party/WebKit/Source/platform/SharedBuffer.h
@@ -37,6 +37,8 @@
 
 namespace blink {
 
+class WebProcessMemoryDump;
+
 class PLATFORM_EXPORT SharedBuffer : public RefCounted<SharedBuffer> {
 public:
     enum : unsigned { kSegmentSize = 0x1000 };
@@ -102,6 +104,8 @@ public:
 
     bool isLocked() const;
 
+    void onMemoryDump(const String& dumpPrefix, WebProcessMemoryDump*) const;
+
 private:
     SharedBuffer();
     explicit SharedBuffer(size_t);