Gallery2: Fix the string can't  be translated in Gallery2.

The string is defined in FilterDrawRepresentation.java with English.

Extract this string into source.xml file and get it by getString().

CR-fixed: 623893

Change-Id: Ied7afc964555cfd752af306742be69eba4a41349
Merge "Gallery2: Fix the string can't  be translated in Gallery2." into du44