[Sync] Rework unit tests for ChromeInvalidationClient

In particular, add unit tests that would have caught bug 139424.

Dep-inject InvalidationClient into ChromeInvalidationClient.

Use the function name 'UpdateRegisteredIds' consistently.

Replace some mocks with fakes.

BUG=139424


Review URL: https://chromiumcodereview.appspot.com/10827133

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@150665 0039d316-1c4b-4281-b951-d872f2087c98
  virtual void Start() {}

  virtual void Start() {}
