[Android] Cache Java-based histogram lookup through RecordHistogram

Avoid JNI string translation for each histogrom update routed through
RecordHistogram by caching the histogram lookup. Use the Java string
handle as the key.

BUG=442300

Review URL: https://codereview.chromium.org/867063006

Cr-Commit-Position: refs/heads/master@{#313174}
2 files changed