Alphabetize JavaScript extern declarations for Android GSA.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=82479459
PlaceholderReference implements CharSequence but violates its contract for toString, so the change to JsMessage should not have been made.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=82514429