ResourceFetcher declines blocked image read instead of deferring.

Before this patch, the <img> elements having blocked URL as their src leaked, as its loader never completes.

This patch changes ResourceFetcher::requestImage()'s behavior to decline blocked URL image load instead of deferring it. Previously, they were set as DeferredByClient, but no code path exist to actually load those "deferred" resources when they are unblocked.

BUG=270000

Review URL: https://chromiumcodereview.appspot.com/22918024

git-svn-id: svn://svn.chromium.org/blink/trunk@156819 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Split Element::recalcStyle into recalcOwnStyle and recalcChildStyle

recalcStyle has become too big, by moving around the local variables based on the
scope where they're needed we can move most of the function out into recalcOwnStyle
where your own style is updated and recalcChildStyle where the style of your
children is calculated.

I also renamed the Detach StyleChange value to be Reattach since that's what it
really means.

There should be no behavior change, I just refactored the code.

Review URL: https://chromiumcodereview.appspot.com/23592004

git-svn-id: svn://svn.chromium.org/blink/trunk@156820 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Rename ComposedShadowTreeWalker to ComposedTreeWalker.

The motivation is to use the terminology the shadow DOM spec is using.

BUG=None

Review URL: https://chromiumcodereview.appspot.com/23669002

git-svn-id: svn://svn.chromium.org/blink/trunk@156822 bbb929c8-8fbe-4397-9dbb-9b2b20218538
ElementShadow::addShadowRoot should use lazyReattachIfAttached

The if statement is identical to calling lazyReattachIfAttached.

Review URL: https://chromiumcodereview.appspot.com/23560004

git-svn-id: svn://svn.chromium.org/blink/trunk@156823 bbb929c8-8fbe-4397-9dbb-9b2b20218538
WebCrypto: Add the KeyPair interface.

Spec: https://dvcs.w3.org/hg/webcrypto-api/raw-file/tip/spec/Overview.html#keypair

BUG=245025

Review URL: https://chromiumcodereview.appspot.com/23617006

git-svn-id: svn://svn.chromium.org/blink/trunk@156824 bbb929c8-8fbe-4397-9dbb-9b2b20218538