Avoid Text layout being triggered unnecessarily

Avoid Text layout being triggered unnecessarily

Text was quite often layed out twice during construction due to
geometry changes, and often at run time due to other geometry changes.
This change checks for cases which do not require relayouting and
drops out early.  These are easier to detect than trying to have a
single giant if statement covering all the positive combinations.

Change-Id: I2deb2ab52d35b3d02bced698d05fef91c9e2f745
Reviewed-by: Michael Brasser <michael.brasser@nokia.com>