[Android] Record UMA metrics after native initialization completes.

Discoverd that we never got LibraryLoader.NativeLibraryHack in UMA
histograms server. Found that's because UMA session was not started
yet right after native libraries are loaded.

By delaying recording until UMA session is started, these stats
shown up in chrome://histograms.

BUG=311644

Review URL: https://codereview.chromium.org/452923004

git-svn-id: http://src.chromium.org/svn/trunk/src/base@289022 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Revert of Adds some CHECKs to MessagePumpMojo (https://codereview.chromium.org/454433003/)

Reason for revert:
Speculative revert, attempting to diagnose timing out Blink layout tests on Windows.

Original issue's description:
> Adds some CHECKs to MessagePumpMojo
> 
> The thread watcher appears to be kicking on when we're trying to
> remove a handle. Not sure why. This converts some DCHECKs to CHECKs
> and fixes handling of the deadline. I suspect none of this will help,
> but it's worth a shot.
> 
> BUG=399769
> TEST=none
> R=darin@chromium.org
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=288949

TBR=darin@chromium.org,sky@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=399769

Review URL: https://codereview.chromium.org/461133002

git-svn-id: http://src.chromium.org/svn/trunk/src/base@289057 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Pass display names for uploaded content URI files

The display names are missing for content URI files.
That will cause some upload to fail.
This CL translates the content URI to displayed name and passes them to native code.

BUG=402537

Review URL: https://codereview.chromium.org/450003002

git-svn-id: http://src.chromium.org/svn/trunk/src/base@289102 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Re-land: base: Introduce an explicit call for reducing emulated discardable memory usage.
    
This removes the use of memory pressure signals from discardable memory
system and instead introduces an explicit call for reducing emulated
discardable memory that the renderer can call when all widgets are hidden
until we have a better mechanism in place.
    
BUG=398087
TEST=base_unittests,content_browsertests

Review URL: https://codereview.chromium.org/448173002

git-svn-id: http://src.chromium.org/svn/trunk/src/base@289127 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Update presubmit files to send windows tryjobs to swarming bots, now that the CQ has switched over.

R=avi@chromium.org

Review URL: https://codereview.chromium.org/461313002

git-svn-id: http://src.chromium.org/svn/trunk/src/base@289157 4ff67af0-8c30-449e-8e8b-ad334ec8d88c