GitLab

This CL:
1- Updates the tabStripLegacyCoordinator to use Browser
   instead of TabModel.
2- Update TabStripController to use Browser instead of tabModel:
  - Change methods & variables to be more suitable to the usage of
    webStateList.
  - Change the type of indices related to the WebStateList to int.
  - Get the dispatchers from the browser instead of getting them
    from the initializer.
  - Remove initializeTabArrayWithNoModel, as there was no way to
    provide the controller no TabModel earlier, which means that
    was a dead code.
  - Updates the test to use TestBrowser instead of the fake tabModel.

Bug: 1049918, 1048683
Change-Id: I4183ce90df9dafd0182c4fa9f03834f21f507cf6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2043077
Commit-Queue: Mohammad Refaat <mrefaat@chromium.org>
Reviewed-by: Rohit Rao <rohitrao@chromium.org>
Reviewed-by: Mark Cogan <marq@chromium.org>
Cr-Commit-Position: refs/heads/master@{#742894}