Add GYP target for sk_tool_utils.* component.

This declares a static library target in gyp/sk_tool_utils.gyp, so other
targets can depend directly on it instead of including the source file
in their source lists.

BUG=None
TEST=make all
R=mtklein@google.com

Author: tfarina@chromium.org

Review URL: https://codereview.chromium.org/348623006
6 files changed