Bug 1028835 - [dolphin][flame] video list display abnormal for a while w...

...hen switch between landscape mode and portrait mode
There is no longer any need to check twice since if the original string doesn't need truncation the function would have returned above. 
Also, in the original code, 'ellipsisAt' (where to put the ellipsis in the 'truncated' string) was being set to the first character on the last allowable line that the string can wrap to. This was prematurely truncating the string; it can be truncated at the last character of the line.