Reports UMA data for bytes fetched over the network for used and
unused prerenders.  It also reports on the total number of bytes
fetched for that profile since the last prerender report.

This gives us insight into the balance of used vs wasted prerenders.
Understanding the ratio of wasted prerender bytes to total bytes gives
us a better understanding of whether we need an option to disable
prerender on mobile networks.

BUG=334602

Review URL: https://codereview.chromium.org/160513002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251316 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251316
Files.app add multi-profile test with maximum number of profiles.

BUG=341224

Review URL: https://codereview.chromium.org/163183002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251317 0039d316-1c4b-4281-b951-d872f2087c98
Use NSS_ENABLE_ECC=1 for instrumented NSS builds.

This more closely matches Ubuntu build options, and fixes at least some of
NSS-related test failures.

BUG=313751
TBR=glider@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/163053004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251318 0039d316-1c4b-4281-b951-d872f2087c98
Files.app: filter out zip archives mounted in other profiles.

BUG=336124

Review URL: https://codereview.chromium.org/164183004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251319 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251319
[IME] Releases key events to Chromium's default behavior if no handler defined in the active IME extension.

BUG=337082
TEST=Locally verified in sandbox.

Review URL: https://codereview.chromium.org/162973002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251320 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251320