cc: Abstract out proxy timing history

Pulling this out into a separate class lets it be reused by SingleThreadProxy.

BUG=329552

Review URL: https://codereview.chromium.org/154163005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251471 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/cc/cc.gyp b/cc/cc.gyp
index 684e6a5..f7632ce 100644
--- a/cc/cc.gyp
+++ b/cc/cc.gyp
@@ -439,6 +439,8 @@
         'trees/occlusion_tracker.h',
         'trees/proxy.cc',
         'trees/proxy.h',
+        'trees/proxy_timing_history.cc',
+        'trees/proxy_timing_history.h',
         'trees/quad_culler.cc',
         'trees/quad_culler.h',
         'trees/single_thread_proxy.cc',