Update all the client code to use a single WebThemeEngine.h header.

R=jamesr@chromium.org, piman@chromium.org
BUG=327471

Review URL: https://codereview.chromium.org/155453002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250851 0039d316-1c4b-4281-b951-d872f2087c98
Warm up EnumSystemLocalesEx() for Flash Player.

Land the patch on behalf of Ye Liu <cbakgly@gmail.com>

The original CL is:
https://codereview.chromium.org/137893002/
(All the three reviewers on the TBR line have LG-ed that CL.)

TBR=piman@chromium.org,jschuh@chromium.org,yzshen@chromium.org
BUG=None

Review URL: https://codereview.chromium.org/161263002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250852 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 250852
Do not include PDF reader assets for platforms with no plugins.

BUG=326023

Review URL: https://codereview.chromium.org/160693002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250853 0039d316-1c4b-4281-b951-d872f2087c98
Prefixed EME: Fire special KeyError when a persistent session is closed.

BUG=340859

Review URL: https://codereview.chromium.org/150203014

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250854 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 250854