Switch libbcc to start using MetadataExtractor.

BUG=6051742

This reduces code duplication, and makes us a client of our own helper library.
It also helps to fix a potential issue that can come up with older bitcode
containing only ForEach signatures and not names (something that was fixed in
MetadataExtractor, but not libbcc). We no longer look at metadata nodes at all
from libbcc.

Change-Id: I5cdacec82e4cd164f1aec5aa28a5e82feb9cfc15
diff --git a/Android.mk b/Android.mk
index 079e73a..e3948c8 100644
--- a/Android.mk
+++ b/Android.mk
@@ -148,7 +148,7 @@
   libLLVMCore \
   libLLVMSupport
 
-LOCAL_SHARED_LIBRARIES := libdl libcutils libutils libstlport
+LOCAL_SHARED_LIBRARIES := libbcinfo libdl libcutils libutils libstlport
 
 # Modules that need get installed if and only if the target libbcc.so is
 # installed.
@@ -245,6 +245,8 @@
   libcutils \
   libutils
 
+LOCAL_SHARED_LIBRARIES := libbcinfo
+
 LOCAL_LDLIBS := -ldl -lpthread
 
 # Generate build stamp (Build time + Build git revision + Build Semi SHA1)