@IntDef cleanup in the chrome/java

@IntDef/@StringDef annotation are preferred way for declaring
set of String/int values:

1. they need less space in APK than enum, see
https://developer.android.com/topic/performance/reduce-apk-size#remove-enums
2. they give more control over allowed values than "static final" values

Main goal of patch is writing "static final" values, enum
and some classes in one common @IntDef/@StringDef form:

1. with @IntDef/@StringDef first, @Retention second
   and related @interface third
2. with values inside @interface
3. with NUM_ENTRIES declaring number of entries if necessary
4. with comment about numbering from 0 without gaps when necessary
5. with @Retention(RetentionPolicy.SOURCE)
6. without "static final" in the @interface

Additionally there are done some other trivial cleanups.

Change-Id: Id50845175a85cb5fc5919c8b79c1cd492f0d994d
Reviewed-on: https://chromium-review.googlesource.com/1136879
Commit-Queue: Tommy Nyquist <nyquist@chromium.org>
Reviewed-by: Tommy Nyquist <nyquist@chromium.org>
Cr-Commit-Position: refs/heads/master@{#576172}
20 files changed