[Telemetry] Increase memconsumer usage to 20MB.

BUG=None
R=bulach@chromium.org, qsr@chromium.org

Review URL: https://codereview.chromium.org/26273005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228746 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 228746
Added a browser test of the print preview dialog size for Chrome apps.

The added PrintPreviewShouldNotBeTooSmall test verifies that the print
preview dialog is big enough to be usable even when printing small
application windows. Because the print preview dialog is currently
limited to the size of the window being printed on all platforms but
OS X, this test currently fails on all platforms but OS X.

BUG=none

Review URL: https://codereview.chromium.org/26678004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228747 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 228747