DialerStats: track how frequently contact images are present on the call detail page

For retail devices (and installer builds), introduce tags to be read
by a separate, additional, package.

This will not be read or collected in any community (nightly/M/etc) or
self-built build.

Change-Id: Ic06b09eb4667297abd44aa11b504088a91cd5102
Merge branch 'cm-11.0' into kk_mkt

Conflicts:
	src/com/android/dialer/cmstats/DialerStats.java

Change-Id: Id46c8c841761169a5c6769d9d834d5e0c4b8e118
Revert "DialerStats: track how frequently contact images are present on the call detail page"

This reverts commit d6e4f35eaa215d6e91400f749d9c92d57a16a7d6.

Conflicts:
	src/com/android/dialer/cmstats/DialerStats.java

Change-Id: I446740694a2e2e4a1b4fe1ef8580fa47738c47ae