Web MIDI: make naming convention be consistent
Naming cleanup based on following rules:
- MidiFooBar ... use this style to be consistent with chromium
- WebMIDIFooBar ... Web API name related things, or names in blink
- MIDIFooBar ... APIs and structures defined by each operating systems
Other cleanup:
- Modify some TODO(crogers) to TODO(toyoshim)
- Add some crbug links.
- Remove some obsolete UI TODOs related to infobars
BUG=none
TEST=build for all platforms
Review URL: https://codereview.chromium.org/
151343002
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@248686 0039d316-1c4b-4281-b951-d872f2087c98