Fix style errors in core/editing/Editor.cpp

This patch fixes style errors in core/editing/Editor.cpp for preparation of decoupling spell checker and Editor class.

Another patch will add SpellChecker.cpp and SpellChecker.h as copy of Editor.cpp and Editor.h.

BUG=n/a
TEST=n/a; no behavior changes.
R=tkent@chromium.org

Review URL: https://codereview.chromium.org/26627005

git-svn-id: svn://svn.chromium.org/blink/trunk@159302 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Support currentTransform in 2D Canvas.

Canvas v5 has a currentTransform that is an SVGMatrix.
http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#dom-context-2d-currenttransform

[Immutable] extended attribute is used, because canvas must not change CTM in
the following case.
    var matrix = context.currentTransform;
    matrix.a = 2;

BUG=277107
TEST=fast/canvas/canvas-currentTransform.html

Review URL: https://codereview.chromium.org/24233004

git-svn-id: svn://svn.chromium.org/blink/trunk@159303 bbb929c8-8fbe-4397-9dbb-9b2b20218538
Copy Editor.{cpp,h} to SpellChecker.{cpp,h}

This patch copies Source/core/editing/Editor.{cpp,h} into Source/core/editing/SpellChecker.{cpp,h} for decoupling Editor and spell checker.

Another patch will complete decoupling.

BUG=n/a
TEST=n/a; No behavior changes.
R=tkent@chromium.org

Review URL: https://codereview.chromium.org/26795002

git-svn-id: svn://svn.chromium.org/blink/trunk@159304 bbb929c8-8fbe-4397-9dbb-9b2b20218538