Mms: Add resend function for message

Change-Id: Ia7344dba3a538f67a7e8e77f49e3dc123a89545e
Signed-off-by: Arnav Gupta <championswimmer@aokp.co>

Conflicts:
	src/com/android/mms/ui/ComposeMessageActivity.java
Mms: Share image/video files via Messaging from file explorer

When we're handling Intent.ACTION_SEND_MULTIPLE, the type passed
in is "*/*", and share uri will look like this: "file:///" if
share from file explorer. So message application can not identify
the share file's type.

Use MediaFile's function to identify the share file's type and set
attachment.

CRs-Fixed: 496743

Change-Id: Icbf37589fde631a385d548fe86d1ee18aea4a7c8