Make a BrowserPluginSpecific test a MimeHandlerViewTest

All GuestViews except for MimeHandlerViewGuest are now implemented based on
cross-process frames. There is however a hadnful of browser tests which are not
MimeHandlerViewTest but still use BrowserPlugin.

This CL will
  1- Change the MimeHandlerViewTest from parameteric to normal test.
  Essentially, the UseCrossProcessFramesForGuest flag is unrelated to
  the MimeHandlerViewGuest. There is a separate flag for that matter
  which is "MimeHandlerViewInCrossProcessFrame" and will be added
  eventually when the a first version of MimeHandlerViewGuest based on
  cross-process frames is implemented on ToT.

  2- Move WebViewBrowserPluginSpecificTest.AcceptTouchEvents to
  MimeHandlerViewTest. This involves overhauling the test test is also
  modified to load MimeHandlerViewGuest instead of WebViewGuest.

The short-term plan is to change all such (BrowserPluginSpecific) tests
to become MimeHandlerViewBrowserPluginSpecificTest. The longer term goal
is to remove all such tests when MimeHandlerViewInCrossProcessFrames
is shipped.

Bug: 659750, 533069, 330264
Change-Id: Icad9ddd1f2d1e6851b20f6c0d923dd2192b7dcec
Reviewed-on: https://chromium-review.googlesource.com/1161745
Commit-Queue: Ehsan Karamad <ekaramad@chromium.org>
Reviewed-by: Ehsan Karamad <ekaramad@chromium.org>
Reviewed-by: Kevin McNee <mcnee@chromium.org>
Cr-Commit-Position: refs/heads/master@{#580655}
3 files changed