Add scripts for running LLVM coverage

tools/llvm_coverage_build

+#!/bin/bash
+# Copyright (c) 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+# Build Skia for use with LLVM's coverage tools.
+#
+# $ tools/llvm_coverage_build [any other flags to pass to make...]
+#
+# This script assumes the use of Clang >=3.6.
+#
+set -e
+
+export CC="$(which clang)"
+export CXX="$(which clang++)"
+
+if [[ -z "${CC}" ]] || [[ -z "${CXX}" ]]; then
+  echo "Couldn't find Clang on this machine!"
+  exit 1
+fi
+
+echo "CC=$CC"
+echo "CXX=$CXX"
+$CC --version
+
+export GYP_DEFINES="skia_warnings_as_errors=0 skia_clang_build=1"

[mtklein, 2015/07/01 20:17:37]

Is needing to disable warnings-as-errors due to Clang or specifically coverage?

[borenet, 2015/07/06 12:06:35]

Clang.  I have 3.6.0 on my machine and get these warnings:

../../src/core/SkRWBuffer.cpp:312:12: error: 'getPosition' overrides a member
function but is not marked 'override' [-Werror,-Winconsistent-missing-override]
    size_t getPosition() const {
           ^
../../include/core/SkStream.h:157:12: note: overridden virtual function is here
    size_t getPosition() const override = 0;
           ^
../../src/core/SkRWBuffer.cpp:316:10: error: 'seek' overrides a member function
but is not marked 'override' [-Werror,-Winconsistent-missing-override]
    bool seek(size_t position) {
         ^
../../include/core/SkStream.h:158:10: note: overridden virtual function is here
    bool seek(size_t position) override = 0;
         ^
../../src/core/SkRWBuffer.cpp:325:10: error: 'move' overrides a member function
but is not marked 'override' [-Werror,-Winconsistent-missing-override]
    bool move(long offset) {
         ^
../../include/core/SkStream.h:159:10: note: overridden virtual function is here
    bool move(long offset) override = 0;
         ^

+export BUILDTYPE=Coverage
+make $@