Build in support for Clang static analysis framework.

Bug: 13243591
Bug: 13287788

These defines are provided by the general Clang makefiles, but we
missed the original (on by default) configuration option there.

Change-Id: Ic12349f97c01112d190e43ba9d18b09255d4308c
diff --git a/lib/FrontendTool/Android.mk b/lib/FrontendTool/Android.mk
index 2496f6b..5816095 100644
--- a/lib/FrontendTool/Android.mk
+++ b/lib/FrontendTool/Android.mk
@@ -17,6 +17,9 @@
 clang_frontend_tool_SRC_FILES := \
   ExecuteCompilerInvocation.cpp
 
+LOCAL_CFLAGS += -DCLANG_ENABLE_STATIC_ANALYZER
+LOCAL_CFLAGS += -DCLANG_ENABLE_REWRITER
+
 LOCAL_SRC_FILES := $(clang_frontend_tool_SRC_FILES)
 
 include $(CLANG_HOST_BUILD_MK)