Support for high-resolution contact photos.

Rather than getting a bitmap directly from the gallery app, with
this change we create a temporary file and request that the photo
be stored there.  This avoids running into bundle size limits when
passing large, uncompressed bitmaps back from the gallery.

After reading the photo out into the Contacts app, we use the
openAssetFile API to stream the large photo data into the
Contacts Provider.  Note that we do this rather than having Gallery
write directly to the provider because we have no guarantee that
the Gallery (or substitute) app has WRITE_CONTACTS permission.

In the Contact Editor, the image is not permanently stored until
the contact is saved.  This avoids needing special logic to handle
the case where the contact is newly-created.

Fix bug 5907233 en passant... the vestiges of some partially-
expunged code were causing the ContentEditorFragment to not
apply a selected photo.

Bug: 5786849
Bug: 5907233
Change-Id: Ic0cabaa50c08d6a9a0b730698c92f4092192438a