Use transforms by default in layout geometry mapping

Instead of kUseTransforms from callers or forced by the implementation,
this CL make it by default. kIgnoreTransforms should be used if the
caller doesn't want transforms in some special cases.

To avoid accidentally changing the behavior, I created the final patch
in the following steps:
Step 1:
a) Added kIgnoreTransforms along with kUseTransforms in MapCoordinatesFlags;
b) Removed the default parameter values of MapCoordinatesFlags from
   geometry mapping functions;
c) Added DCHECK((mode & kIgnoreTransforms) || (mode & kUseTransforms)) to
   ensure that the caller must explicitly choose between kIgnoreTranforms
   and kUseTransforms;
d) Modified all callers to explicitly specify kIgnoreTransforms or
   kUseTransforms based on their original behavior.
e) Made all tests pass
https://chromium-review.googlesource.com/c/chromium/src/+/1621707/3

Step 2:
a) Remove kUseTransforms from MapCoordinatesFlags
b) Remove DCHECK((mode & kIgnoreTransforms) || (mode & kUseTransforms))
   from geometry mapping functions
c) Remove kUseTransforms from call sites

This CL should not change any existing behavior.

Change-Id: I860cde66f47f0c72509a21615afaefcb4851e4d6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1621707
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Reviewed-by: Philip Rogers <pdr@chromium.org>
Reviewed-by: Fernando Serboncini <fserb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#663901}