Compute the keyTimes index correctly for discrete (values) animations

The last value is allowed to be non-one for discrete mode animations (but
not for linear and spline mode animations).

TEST=svg/animations/animate-elem-{14,18}-t-drt.html
BUG=350318

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=169211

Review URL: https://codereview.chromium.org/197283002

git-svn-id: svn://svn.chromium.org/blink/trunk@169351 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Enable back 4 tests for Debug builds.

BUG=352035
TBR=loislo@chromium.org

Review URL: https://codereview.chromium.org/201893002

git-svn-id: svn://svn.chromium.org/blink/trunk@169352 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Need new layout test baseline after modified compiler message.

BUG=351658
TBR=rossberg@chromium.org

Review URL: https://codereview.chromium.org/201843002

git-svn-id: svn://svn.chromium.org/blink/trunk@169353 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: track stylesheets by document, not local frame.

R=lushnikov@chromium.org, vsevik@chromium.org

Review URL: https://codereview.chromium.org/201683002

git-svn-id: svn://svn.chromium.org/blink/trunk@169354 bbb929c8-8fbe-4397-9dbb-9b2b20218538