Add GN rules for building instrumented libraries.

BUG=585127

Review-Url: https://codereview.chromium.org/2103683002
Cr-Original-Commit-Position: refs/heads/master@{#406452}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: fba9bdbfc9ccc9c7909e1bd4784bcb05df9da649

config/BUILD.gn

@@ -403,6 +403,9 @@ config("executable_config") {
   if (prebuilt_instrumented_libraries_available) {
     configs += [ "//third_party/instrumented_libraries:prebuilt_ldflags" ]
   }
+  if (use_locally_built_instrumented_libraries) {
+    configs += [ "//third_party/instrumented_libraries:locally_built_ldflags" ]
+  }
 }
 
 # Shared library configs -------------------------------------------------------
@@ -424,6 +427,9 @@ config("shared_library_config") {
   if (prebuilt_instrumented_libraries_available) {
     configs += [ "//third_party/instrumented_libraries:prebuilt_ldflags" ]
   }
+  if (use_locally_built_instrumented_libraries) {
+    configs += [ "//third_party/instrumented_libraries:locally_built_ldflags" ]
+  }
 }
 
 # Add this config to your target to enable precompiled headers.

config/sanitizers/BUILD.gn

@@ -57,7 +57,8 @@ group("deps_no_options") {
       data += [ "$clang_base_path/lib/libstdc++.so.6" ]
     }
 
-    if (use_prebuilt_instrumented_libraries) {
+    if (use_prebuilt_instrumented_libraries ||
+        use_locally_built_instrumented_libraries) {
       deps += [ "//third_party/instrumented_libraries:deps" ]
     }
     if (use_custom_libcxx) {

config/sanitizers/sanitizers.gni

@@ -38,6 +38,10 @@ declare_args() {
   # GCS.
   use_prebuilt_instrumented_libraries = false
 
+  # Use dynamic libraries instrumented by one of the sanitizers instead of the
+  # standard system libraries. Set this flag to build the libraries from source.
+  use_locally_built_instrumented_libraries = false
+
   # Enable building with SyzyAsan which can find certain types of memory
   # errors. Only works on Windows. See
   # https://github.com/google/syzygy/wiki/SyzyASanHowTo

toolchain/gcc_toolchain.gni

@@ -494,6 +494,7 @@ template("gcc_toolchain") {
       use_drfuzz = false
       use_libfuzzer = false
       use_prebuilt_instrumented_libraries = false
+      use_locally_built_instrumented_libraries = false
       use_sanitizer_coverage = false
     }