Add support for text geometry

Add support for text geometry

Added the following requested API's for text  geometry :

GetTextSize();
GetTextPosition();

above API's could return a list of values in case of :
1-multiline, each line in a separate value.
2-mixed text of LTR & RTL, each contiguous block of the same direction has a separate value.

note that above API's returns values based on the current rendered text position/size.

Change-Id: I1ee9d26954d529bb81c72647dbc9f09ccc8e35ac