GN: Introduce templates.

webrtc/modules/desktop_capture/BUILD.gn

Index: webrtc/modules/desktop_capture/BUILD.gn
diff --git a/webrtc/modules/desktop_capture/BUILD.gn b/webrtc/modules/desktop_capture/BUILD.gn
index 61a3de2fe16379bccc07d2dd054fb62087e39dd2..dca6a29bb5a9abc46b58022850e18201341901cc 100644
--- a/webrtc/modules/desktop_capture/BUILD.gn
+++ b/webrtc/modules/desktop_capture/BUILD.gn
@@ -12,7 +12,7 @@ import("../../build/webrtc.gni")
 use_desktop_capture_differ_sse2 =
     !is_ios && (current_cpu == "x86" || current_cpu == "x64")
 
-source_set("primitives") {
+rtc_source_set("primitives") {
   sources = [
     "desktop_capture_types.h",
     "desktop_frame.cc",
@@ -26,7 +26,7 @@ source_set("primitives") {
   public_configs = [ "../..:common_inherited_config" ]
 }
 
-source_set("desktop_capture") {
+rtc_source_set("desktop_capture") {
   sources = [
     "cropped_desktop_frame.cc",
     "cropped_desktop_frame.h",
@@ -154,7 +154,7 @@ source_set("desktop_capture") {
   if (is_clang && !is_nacl) {
     # Suppress warnings from Chrome's Clang plugins.
     # See http://code.google.com/p/webrtc/issues/detail?id=163 for details.
-    configs -= [ "//build/config/clang:find_bad_constructs" ]
+    configs_suppressions += [ "//build/config/clang:find_bad_constructs" ]
   }
 
   deps = [
@@ -171,7 +171,7 @@ source_set("desktop_capture") {
 if (use_desktop_capture_differ_sse2) {
   # Have to be compiled as a separate target because it needs to be compiled
   # with SSE2 enabled.
-  source_set("desktop_capture_differ_sse2") {
+  rtc_source_set("desktop_capture_differ_sse2") {
     visibility = [ ":*" ]
     sources = [
       "differ_block_sse2.cc",