Revert 105667 - Send important client side event information to the server. We create a class cal...

Revert 105667 - Send important client side event information to the server. We create a class called DebugInfoEventListener which implements 2 interfaces. one being the syncmanager::observer to observe events from syncmanager.
The other being DebugInfoGetter so that syncer can call this class to give the debug information in protobuf format.
The implementation of this class uses a queue. And it limits the number of events to 6. if more than 6 events are in the queue we delete the oldest event.
Also we send this information to the server only once per sync cycle during the first getudpdates command.

also includes the unit test.
BUG=100058
TEST=

Review URL: http://codereview.chromium.org/8189003

TBR=lipalani@chromium.org
Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=105680