Lazily instantiate Geolocation permission manager maps.

Delay creating the bidirectional maps needed to handle Geolocation
permission requests until actually used. To avoid instantiating a
pair of Persistent<> references when doing so, move the wrapper
private object to the Oilpan heap.

R=haraken,tkent
BUG=340522

Review URL: https://codereview.chromium.org/1339353002

git-svn-id: svn://svn.chromium.org/blink/trunk/public@202336 bbb929c8-8fbe-4397-9dbb-9b2b20218538
1 file changed