blimp: Fix input events sent from the client to the engine

The BlimpInputHandlerWrapper incorrectly sets the input events handles by
the compositor as consumed, causing duplicate events being sent to the
compositor and the renderer on the engine.
Don't send events handled or dropped by the compositor to the engine.

Review URL: https://codereview.chromium.org/1591083002

Cr-Commit-Position: refs/heads/master@{#369850}
1 file changed