CSP: Ship hash and nonce expressions, and the 'frame-ancestors' directive.

This matches Firefox's behavior (see [1]). Hooray for interoperation!

Intent to Ship thread: https://groups.google.com/a/chromium.org/d/msg/blink-dev/rCiwMvGG8IY/MgRtHrkQfgMJ

[1]: https://bugzilla.mozilla.org/show_bug.cgi?id=979580

Review URL: https://codereview.chromium.org/220343005

git-svn-id: svn://svn.chromium.org/blink/trunk@170551 bbb929c8-8fbe-4397-9dbb-9b2b20218538
[CSS Grid Layout] Implementation of the grid-template shorthand.

This shorthand sets the values for the grid-template-columns, 
grid-template-rows and grid-template-areas, so the 
implementation tries to reuse as much available parsing 
functions as possible.

The "parsingGridTrackList" was refactored to return a 
CSSValue and let the "parseValue" function to assign the 
property value. The "forwardSlash" operator is now valid 
when the track-list clause is part of a shorthand. The  
"parseValue" function checkouts that only additional 
clauses are allowed when processing shorthands; the 
grid-columns-rows-get-set.html tests was modified to verify 
this.

The "parseGridTemplateAreas" was refactored too, in order 
to process single areas's rows. This is very useful for the 
gris-template secondary syntax, which mixes areas and rows 
values.


Finally, the "parseGirdLineNames" function was modified as 
well by defining an new argument to concatenate head/tail 
custom-ident elements and ensure the identList is at the 
heading index, since it's now possible the parseList was 
rewound.

The implementation of the grid-template shorthand tries 
first to match the <grid-template-columns> / <grid-template-rows> 
syntax, failing back to the secondary syntax if needed. 
This approach requires to rewind the parseList but it 
produces a clearer code.
 
TEST=fast/css-grid-layout/grid-template-shorthand-get-set.html

BUG=79180

Review URL: https://codereview.chromium.org/149373004

git-svn-id: svn://svn.chromium.org/blink/trunk@170552 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Replace NativeImageSkia usage with SkBitmap in ImageFrame

Make ImageFrame store an SkBitmap directly instead of indirectly via
NativeImageSkia.
The direct effect is less indirections in ImageFrame, but this allows
making NativeImageSkia more immutable-looking since the SkBitmap&
accessor and setDataComplete() method can be removed.

Review URL: https://codereview.chromium.org/170463002

git-svn-id: svn://svn.chromium.org/blink/trunk@170553 bbb929c8-8fbe-4397-9dbb-9b2b20218538