Refactor BUILD.gn so can easily be embedded in other projects

1.
BUILD.gn: Don't use the extra Chromium clang warnings

Also removes the unused .gn secondary_sources.

2.

Move fuzzers in test/ instead of testing/

This frees up testing/ to be the git subtree of Chromium's src/testing/
that contains test.gni, gtest, gmock and libfuzzer

3.

DEPS: get the whole testing/ subtree of Chromium

4.

BUILD.gn: Simplify the standalone gtest targets

These targets definitions are inspired from ANGLE's and add a variable
that is the path of the googletest directory so that it can be made
overridable in future commits.

6.

BUILD.gn: Add overridable variables for deps dirs

This avoids hardcoded paths to dependencies that make it hard to
integrate SPIRV-Tools in other GN projects.

1 files changed, 25 insertions, 0 deletions

diff --git a/build_overrides/spirv_tools.gni b/build_overrides/spirv_tools.gni
new file mode 100644
index 000000000..24aa033d7
--- /dev/null
+++ b/build_overrides/spirv_tools.gni
@@ -0,0 +1,25 @@
+# Copyright 2018 Google Inc. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# These are variables that are overridable by projects that include
+# SPIRV-Tools. The values in this file are the defaults for when we are
+# building from SPIRV-Tools' repository.
+
+# Whether we are building from SPIRV-Tools' repository.
+# MUST be set to false in other projects.
+spirv_tools_standalone = true
+
+# The path to SPIRV-Tools' dependencies
+spirv_tools_googletest_dir = "//external/googletest"
+spirv_tools_spirv_headers_dir = "//external/spirv-headers"