[DevTools] Fix css layout problem in help screen.

BUG=359473

Review URL: https://codereview.chromium.org/235003003

git-svn-id: svn://svn.chromium.org/blink/trunk@171345 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: [Elements] Reveal TextNode's parent element if the former is whitespace-only

R=pfeldman, yurys
BUG=331363

Review URL: https://codereview.chromium.org/230743006

git-svn-id: svn://svn.chromium.org/blink/trunk@171346 bbb929c8-8fbe-4397-9dbb-9b2b20218538
input.focus() should not change selection.

The api focus() shows different behaviour depending on how the value
    is set. If the value is set using the html "value" attribute and
    focus() is called then text get selected whereas if value is set using
    javascript value IDL attribute and then focus() is called caret appear at end
    of text in the field. All other browser shows same behaviour for both cases by
    displaying caret in input field. This patch removes this bug by initializing
    m_cachedSelection{Start,End} with 0. This way for HTML value attribute case
    the caret will be displayed at the start of input field. Since m_cachedSelection{Start,End}
    has been initialize with 0 so hasCachedSelection() api will always return true and hence
    is removed.

BUG=133242

Review URL: https://codereview.chromium.org/222023002

git-svn-id: svn://svn.chromium.org/blink/trunk@171347 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove UnsafePersistent from V8ValueCache / StringCache.

R=dcarney@chromium.org
BUG=276323

Review URL: https://codereview.chromium.org/206533004

git-svn-id: svn://svn.chromium.org/blink/trunk@171348 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Add expectations for Chromium-side mock scrollbar change

Suppressing future failures from Chromium-side change to mock
scrollbars.  Mac doesn't use mock scrollbars, so this only affects
Windows and Linux.

See: https://codereview.chromium.org/233193006/

TBR=abarth@chromium.org
BUG=362078

Review URL: https://codereview.chromium.org/226363006

git-svn-id: svn://svn.chromium.org/blink/trunk@171349 bbb929c8-8fbe-4397-9dbb-9b2b20218538