[PPAPI] File system hosts can be created with an existing file system.

Added a new constructor to to both PepperFileSystemHost and
PepperFileSystemBrowserHost which sets the host to point to a file
system that has already been opened.

BUG=177017

Review URL: https://codereview.chromium.org/24498002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225685 0039d316-1c4b-4281-b951-d872f2087c98
Cleanup: Remove a few unused data files.

Review URL: https://codereview.chromium.org/24651004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225686 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225685
Disable WebViewTest.AutoSize which is flaky on XP bots.

TBR=fsamuel@chromium.org
BUG=299507
NOTRY=true

Review URL: https://codereview.chromium.org/24963002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@225687 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 225687