fix headers drawing mismatched with bodies upon send on tablet

Two-pane layout runs a stray layout pass upon send (related to
b/7409762). Prevent it from changing existing header positions
until the new body geometry is determined.

Fixing that exposed a separate issue, that conversations shorter
than one screen tall would not draw the new header, ever. Add
manual position refresh calls to newer JS calls that had
previously depended on ContentSizeChangeListener.

Bug: 7404104
Change-Id: I805fc9ab12878a95573316763986d84f89cfd2c0
2 files changed