Move Cursor to platform/

BUG=297477

Review URL: https://codereview.chromium.org/108383002

git-svn-id: svn://svn.chromium.org/blink/trunk@163445 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Consistently use AtomicString for namespaceURI / prefix

Consistently use AtomicString for namespaceURI / prefix. In particular, Node's
lookupPrefix(), lookupNamespaceURI(), lookupNamespacePrefix() now deal with
AtomicStrings.

This avoids needless creation of Strings when we actually need AtomicStrings.
This is one step towards marking the AtomicString(const String&) constructor
explicit.

R=eseidel, haraken
BUG=323739

Review URL: https://codereview.chromium.org/108543003

git-svn-id: svn://svn.chromium.org/blink/trunk@163446 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Fix incorrectly added history entries on script-triggered location change.

committedMultipleRealLoads, given how it's used, should only be set when the second load creates a new history item.

BUG=323574
TEST=Tested manually on google spreadsheets, will land automated test in a separate patch

Review URL: https://codereview.chromium.org/109283002

git-svn-id: svn://svn.chromium.org/blink/trunk@163447 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: Add a checkbox to enable async stacks in the sidebar header.

This also removes the checkbox from the Settings page.

BUG=272416
R=pfeldman, yurys

Review URL: https://codereview.chromium.org/102833003

git-svn-id: svn://svn.chromium.org/blink/trunk@163448 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Move WebScrollbarImpl to platform/

BUG=297477

Review URL: https://codereview.chromium.org/108913003

git-svn-id: svn://svn.chromium.org/blink/trunk@163449 bbb929c8-8fbe-4397-9dbb-9b2b20218538