[Title] Fix the parsing-logic used to collect the harfBuzzRuns

[Title] Fix the parsing-logic used to collect the harfBuzzRuns

[Issue#] N_SE36590

[Problem] Width of any word, containing a complex character after a space, is wrong.

[Cause] There should be one harfBuzzRun created for one word. In the case where the word starts with
        a complex character and there is a space before the word, the first glyph of the complex character
        becomes one harfBuzzRun and the rest of the word is another harfBuzzRun.
        The complex character is not reshaped as expected.

[Solution] Fix the parsing-logic used to collect the harfBuzzRuns, in function HarfBuzzShaper::collectHarfBuzzRuns.
           Update the value of "nextScript" in the for-loop, soon after consuming each character.

[Developer] rashmi.s2@samsung.com