Remove an unused static method

This was added in 44640712f without actually being used.
Merge pull request #789 from mstorsjo/remove-unused-static-func

Remove an unused static method
Add func init for welsfillingPred
Add func init on UT source code
Fix gtest build error when OS=msvc.
Merge pull request #792 from zhilwang/msvc-gtest

Fix gtest build error when OS=msvc.
Merge pull request #791 from zhilwang/intraSad

Add func init for welsfillingPred
add Inter Psub16 MD for screen content
reformat
add calling
reformat
Merge branch 'md_merge13' of https://github.com/sijchen/openh264 into md_merge12

Conflicts:
	codec/encoder/core/src/encoder_ext.cpp