Add ClearLogs button in syncfs-internals

By default the logger keeps 1000 lines, sometimes it's too noisy to run multiple load tests

BUG=none

Review URL: https://codereview.chromium.org/110043003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@240080 0039d316-1c4b-4281-b951-d872f2087c98
[android_webview] Add onPageStarted for data loads with base URLs.

This adds the missing onPageStarted callback.

TEST=AndroidWebViewTest
BUG=327391
Android-only, trybots happy
NOTRY=true

Review URL: https://codereview.chromium.org/110573003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@240081 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 240081