Merge gpu_trace_event back into base/debug/trace_event.

Initial land attempt at http://codereview.chromium.org/6551019/
gpu_trace_event fork at http://codereview.chromium.org/6691013

- gpu_trace_event renamed to base/debug/trace_event and modified as appropriate for base::debug
- Unit Tests implemented for trace_event
- gpu_common library removed (was added only for gpu_trace_event)
- Existing calls to trace_event suffixed with _ETW to make ETW calls (see decisions and incremental plans at end of 6551019)
- GPU trace calls renamed to new calls.
- Tracing switch removed from test_shell, as linux log file support removed.

BUG=79509
TEST=trace_event_win_unittest and about:gpu

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=84284

Review URL: http://codereview.chromium.org/6862002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@84486 0039d316-1c4b-4281-b951-d872f2087c98

base/base.gyp

@@ -117,6 +117,7 @@
         'cpu_unittest.cc',
         'debug/leak_tracker_unittest.cc',
         'debug/stack_trace_unittest.cc',
+        'debug/trace_event_unittest.cc',
         'debug/trace_event_win_unittest.cc',
         'dir_reader_posix_unittest.cc',
         'environment_unittest.cc',

base/base.gypi

@@ -404,7 +404,6 @@
               # regression to page cycler moz.
               'sha1_win.cc',
               'string16.cc',
-              'debug/trace_event.cc',
             ],
           },],
           ['OS=="freebsd" or OS=="openbsd"', {