Reland "Move WebKitPlatformSupportImpl over to content."

In the process rename it BlinkPlatformImpl to avoid conflicts and
confusion with an existing WebKitPlatformSupportImpl class in content.

This step is necessary because WebKitPlatformSupportImpl uses
webkit/common/user_agent/, and we also want to move user_agent to
content.

So this needs to happen first because webkit can't depend on content as
content already depends on webkit, otherwise we would be creating a
circular dependency.

WebURLLoader and WebSocketStreamHandleImpl had to be moved with
WebKitPlatformSupportImpl, because they both uses
WebKitPlatformSupportImpl and vice-versa.

BUG=265753, 338338, 237249
TEST=content_unittests
R=jam@chromium.org
TBR=darin

Review URL: https://codereview.chromium.org/180153012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254507 0039d316-1c4b-4281-b951-d872f2087c98
Replace PO2TS::GetPrimaryAccountId() with SMB::GetAuthenticatedAccountId.

The functionality is the same, just moving the code to a new place.

BUG=333995

Review URL: https://codereview.chromium.org/182523003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254508 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 254508
Update string

BUG=281246
TBR=nkostylev@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/178473017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254509 0039d316-1c4b-4281-b951-d872f2087c98
Move away from TabModelList::GetTabModelWithProfile

BUG=341231

Review URL: https://codereview.chromium.org/155513006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254510 0039d316-1c4b-4281-b951-d872f2087c98
Clean up MFYI by adding suppressions for new bugs
TBR=oshima@chromium.org
BUG=329960,348629,348630,347967,331468
NOTRY=true

Review URL: https://codereview.chromium.org/177393003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@254511 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 254511