Updates for recent version of Skia, separate tree.

- compile_and_run_test.sh = how to compile libskia.so with skia.cpp.
- skia.h - Updated to reflect recent changes to Skia API
- skia.cpp Updated for recent changes to Skia API
- test_libskia.c - now C89 compliant.
- skia.h - compiles with -pedantic.
You don't need the newline here in sed. Some implementations of `sed` break and only insert a literal 'n' here which makes the generated gypi unparseable.