Close wrench menu when Media Router Action clicked in Views.
Currently, on |ExecuteAction|, the Media Router dialog is opened and the wrench menu stays open. The menu must be closed with a second click. With this change, the wrench menu closes automatically.
This change also adds a platform delegate to the Media Router Action for platform dependent implementations.
This CL does not include the Cocoa implementation.
BUG=508546
Review URL: https://codereview.chromium.org/
1228223002
Cr-Commit-Position: refs/heads/master@{#339457}