Move FORCE_BUILD_LLVM_COMPONENTS to a defaults module

Instead of extending each module type that needs to handle
FORCE_BUILD_LLVM_COMPONENTS, make it a defaults module that can
be included into any module type.

Test: mmma -j external/clang
Test: mmma -j external/clang FORCE_BUILD_LLVM_COMPONENTS=true
Change-Id: I9ed5913e6747ca68e41c9b12d63bed55fbbee7a2
diff --git a/Android.bp b/Android.bp
index b0d30b5..64b1f40 100644
--- a/Android.bp
+++ b/Android.bp
@@ -165,9 +165,12 @@
     out: ["clang/Basic/Version.inc"],
 }
 
-llvm_cc_library_shared {
+cc_library_shared {
     name: "libclang",
-    defaults: ["clang-defaults"],
+    defaults: [
+        "clang-defaults",
+        "force_build_llvm_components",
+    ],
 
     host_supported: true,