Initiate device scale factor on WebProcess's creation
Initiate device scale factor on WebProcess's creation

[Title] Initiate device scale factor WebProcess's creation
[Issue#] N_SE-41307
[Problem] Sometimes, TouchPaint app drawing point is not matched to touch point
[Cause] On viewport initiation, layout size and initial scale factor are
        calculated incorrectly by uninitiated device scale factor. Device scale
        factor is initiated after rendering logic begins.
[Solution] Initiate device scale factor on WebProcess's creation

Change-Id: Id231b8bb47b6508bbd803f34a7132b07e88172d1

youfoh/webkit-efl,youfoh/webkit-efl,youfoh/webkit-efl,youfoh/webkit-efl,youfoh/webkit-efl,youfoh/webkit-efl,youfoh/webkit-efl,youfoh/webkit-efl,youfoh/webkit-efl,youfoh/webkit-efl,youfoh/webkit-efl