Make sure getAttribute() / setAttribute() callers use AtomicStrings

Make sure getAttribute() / setAttribute() callers use AtomicStrings. Especially,
the DOM API should make sure to request an AtomicString if they call setAttribute()
internally so that the bindings code won't uselessly created a WTF::String from the
v8::String. That String will then implicitly be converted to an AtomicString when
calling setAttribute(), which has a cost.

This is one step towards making the AtomicString(const String&) constructor
explicit.

R=abarth, eseidel, haraken
BUG=323739

Review URL: https://codereview.chromium.org/99333011

git-svn-id: svn://svn.chromium.org/blink/trunk@163293 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Remove TreatNullAs=NullString for URLUtils.href

http://url.spec.whatwg.org/#urlutils

The updated element-attribute-js-null tests pass in Firefox Nightly,
IE11 Release Preview and Opera 12.16.

No other browser passes the URL.href test, because Firefox throws when
setting a non-valid URL, while IE and Opera don't even support the URL
constructor.

BUG=310298

Review URL: https://codereview.chromium.org/105823005

git-svn-id: svn://svn.chromium.org/blink/trunk@163294 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Prevent ASSERTION FAILED !(len & kPageAllocationGranularityOffsetMask) on win.

This can only happen on windows, where kPageAllocationGranularity is 64K. To
ensure this isn't violated, we can't ask for N-1 additonal system pages when
the alignement fails (although that is sufficient from a space perspective to
cover the desired address).  So just ask for N.

This assertion is preventing a webkit roll.
TBR=cevans@chromium.org

Review URL: https://codereview.chromium.org/107133002

git-svn-id: svn://svn.chromium.org/blink/trunk@163295 bbb929c8-8fbe-4397-9dbb-9b2b20218538
IDL compiler: sync Python to r163234

Python side to:
Manage FileSystem callbacks with OwnPtr instead of refcounting
https://codereview.chromium.org/105523002/

This removes the legacy ref count special case for callback
interfaces, so the Python CG is also fully updated.

BUG=323681
NOTRY=true
TBR=haraken

Review URL: https://codereview.chromium.org/107593002

git-svn-id: svn://svn.chromium.org/blink/trunk@163296 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Revert 163292 "Revert 163253 "Move partition page metadata out-o..."

r163295 solved the problem.

> Revert 163253 "Move partition page metadata out-of-line."
> 
> Speculative revert for test failures on Windows 7.
> See http://src.chromium.org/viewvc/chrome?revision=239014&view=revision
> 
> > Move partition page metadata out-of-line.
> > 
> > There are further simplifcations to follow, but with this CL, we realize these
> > benefits:
> > 
> > - Much less memory waste for certain common bucket sizes. The worst case is
> > probably 2048 bytes which is a common allocation size and leads to a 12.5%
> > wastage due to 2048 fitting perfectly in 16384 (partition page size) but us
> > losing an entire 2048 byte chunk due to the 64 byte metadata header. We've
> > now ditched that header.
> > 
> > - Complete removal of re-entrancy from the allocator. Now that the metadata is
> > out-of-line, we don't lose it when freeing system pages. Therefore, we don't
> > need to allocate any space for it on free. It's always there.
> > 
> > - Minor security improvement. It's now not possible to corrupt metadata with
> > any linear buffer overflow or underflow.
> > 
> > BUG=324960
> > 
> > Review URL: https://codereview.chromium.org/99143003
> 
> TBR=cevans@chromium.org
> 
> Review URL: https://codereview.chromium.org/107603002

TBR=cevans@chromium.org,tsepez@chromium.org

Review URL: https://codereview.chromium.org/107633002

git-svn-id: svn://svn.chromium.org/blink/trunk@163297 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Scroll bars continue to scroll when finger leaves the scroll bar.

This patch also ensures that the thumb is deactivated when the finger
is released. Previously this didn't occur on fling start.

Scroll bars become active on tap down instead of scroll begin.

This disables fling for scroll bars.

BUG=324479
TEST=fast/events/touch/gesture/gesture-scrollbar.html, 
fast/events/touch/gesture/gesture-scrollbar-fling.html

Review URL: https://codereview.chromium.org/99013004

git-svn-id: svn://svn.chromium.org/blink/trunk@163298 bbb929c8-8fbe-4397-9dbb-9b2b20218538