Refactoring: Extract StyleSheetCollectionBase from StyleSheetCollection.

This chagne extract StyleSheetCollection bas which carries
two list of stylesheet but nothing else. This class makes sense
since these two lists are the unit of the update operation.
Also, coming change will use this as a unit of cross-document
active sheet collection.

BUG=319151
TEST=none
R=tasak@google.com, esprehn, tasak

Review URL: https://codereview.chromium.org/80243002

git-svn-id: svn://svn.chromium.org/blink/trunk@162443 bbb929c8-8fbe-4397-9dbb-9b2b20218538
IDL compiler: [DependentLifetime] interfaces

V. simple one.

Doc:
https://sites.google.com/a/chromium.org/dev/blink/webidl/blink-idl-extended-attributes#TOC-DependentLifetime-i-

BUG=239771
NOTRY=true

Review URL: https://codereview.chromium.org/80283002

git-svn-id: svn://svn.chromium.org/blink/trunk@162444 bbb929c8-8fbe-4397-9dbb-9b2b20218538
IDL compiler: [DoNotCheckConstants]

Test-only change, as extended attribute supported when initially implemented
constants.

BUG=239771
NOTRY=true
TBR=haraken

Review URL: https://codereview.chromium.org/80303002

git-svn-id: svn://svn.chromium.org/blink/trunk@162445 bbb929c8-8fbe-4397-9dbb-9b2b20218538
IDL compiler: add sequence<Dictionary> argument and simplify type handling

This syncs to r162335:
Add Perl IDL support for method parameter type sequence<Dictionary>
https://codereview.chromium.org/74533003/

...and significantly simplifies the type handling in V8 -> C++ conversions,
by putting all the logic in includes_for_types, instead of splitting it
between includes_for_types and v8_value_to_cpp_value.
This simplifies dicts as well (simple type -> conversion, without also
listing includes) and thus lets us merge 2 dicts (basic types and interface
types).

BUG=257235
BUG=239771
NOTRY=true

Review URL: https://codereview.chromium.org/79223005

git-svn-id: svn://svn.chromium.org/blink/trunk@162446 bbb929c8-8fbe-4397-9dbb-9b2b20218538
IDL compiler: [CustomIsReachable] interfaces

One use: Nodelist.idl

BUG=239771
NOTRY=true

Review URL: https://codereview.chromium.org/78263004

git-svn-id: svn://svn.chromium.org/blink/trunk@162448 bbb929c8-8fbe-4397-9dbb-9b2b20218538