fix rotate + save draft creating multiple drafts

mDraft was not saved upon activity state save, so:
1) its draft ID was lost -> next Save Draft would save anew
2) its sendUri and saveUri were lost -> next Save Draft NPEs

When saving mDraft, amend it with the replyAccount/mode as was
previously done.

Bug: 7411480
Change-Id: Ib19e3d636bae5a4cdba950f40b784b0a544ab07c
1 file changed