[Binding] Use 'operation' term for consistency

Currently 'method', 'function' or 'operation' are used
for operation of WebIDL.
http://www.w3.org/TR/WebIDL/#dfn-operation

This patch replace method and function with operation
where it means operation of WebIDL.

Generated code is exactly same as before.

R=haraken@chromium.org
BUG=239771
TEST=No tests. Refactoring.

Review URL: https://chromiumcodereview.appspot.com/17096009

git-svn-id: svn://svn.chromium.org/blink/trunk@152743 bbb929c8-8fbe-4397-9dbb-9b2b20218538
GIFDecoder: Use index in place of iterator in vector iteration

This is for a terse and easier-to-read code.
Came up during the review of: https://codereview.chromium.org/13980003/

BUG=

Review URL: https://chromiumcodereview.appspot.com/17335014

git-svn-id: svn://svn.chromium.org/blink/trunk@152744 bbb929c8-8fbe-4397-9dbb-9b2b20218538