fixes b/10788190 Change-Id: I11f21d7614fe70781ae2d20ab2947c77843580fa
Add mipmap-xxhdpi launcher icon asset. Remove unneeded drawable-based launcher icon assets while we're at it. Bug: 6718166 Change-Id: I0f9ed4968569e0c2bce44e617a0586f0672d916a