DevTools: [SSP] extract computed style section into computedStylePane

Currently, StylesSidebarPanel has a "sections" object, which among other
sections contains a computed styles section. 

This patch:
- extracts computed section into ComputedStyleSidebarPane
- eliminates isPlaceholder styleRule property
- eliminates computedStyle styleRule property

Note, that "styleRule" refered here is a special object used in the guts of StylesSidebarPane to hold state.

Review URL: https://codereview.chromium.org/708453002

git-svn-id: svn://svn.chromium.org/blink/trunk@185590 bbb929c8-8fbe-4397-9dbb-9b2b20218538
[DevTools] support search in Heap snapshot

a plain search method was implemented in HeapSnapshot.
Search throttler was added for throttling the sequence
of search requests while user typing the search string.

BUG=

Review URL: https://codereview.chromium.org/722913003

git-svn-id: svn://svn.chromium.org/blink/trunk@185592 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: Fix search in highlighted SCRIPT and STYLE

Now that the DOM highlighting is async, search results highlight
can be run against a non-highlighted DOM, which will be detached
as soon as the syntax highlight is completed. This results in
DOM exceptions when removing the search highlights.

R=pfeldman

Review URL: https://codereview.chromium.org/739583002

git-svn-id: svn://svn.chromium.org/blink/trunk@185602 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: CSS outline should report columns correctly.

This patch fixes typo in CSSParser, which reported "columNumbers"
instead of "columnNumbers", and adds a top-down test to verify
functionality.

BUG=432136

Review URL: https://codereview.chromium.org/739863002

git-svn-id: svn://svn.chromium.org/blink/trunk@185603 bbb929c8-8fbe-4397-9dbb-9b2b20218538
DevTools: [SSP] completely eliminate styleRule.isStyleSeparator

This patch continues styles side bar refactoring:
- eliminate styleRule.isStyleSeparator, styleRule.isPseudoId properties
- inline two minor functions in innerRefreshUpdate

With this change, every styleRule would correspond to some
section. (which is not the case currently)

R=vsevik

Review URL: https://codereview.chromium.org/703873003

git-svn-id: svn://svn.chromium.org/blink/trunk@185605 bbb929c8-8fbe-4397-9dbb-9b2b20218538