Adding support for windows viewer build.

# Conflicts:
#	dev/test/premake5.lua

Author: luigi-rosso

skia/viewer/build/windows/dependencies/make_glfw.bat

@@ -11,7 +11,7 @@ pushd .\glfw
 git checkout master
 popd
 
-mkdir -p glfw_build
+mkdir glfw_build
 cd glfw_build
 cmake ../glfw -DBUILD_SHARED_LIBS=OFF
 rem Force compile with /MT, GLFW defaults to /MDd but the rest of our libs expect /MT