Split datasource out of libstagefright

into libdatasource, which contains:
  DataSourceFactory
  (Clear)FileSource
  (Clear)MediaHTTP
  DataURISource
  HTTPBase
  NuCachedSource2

This is needed to break a circular dependency in an upcoming CL.

Test: build, boot

Change-Id: I34d9937235c78f18f51b18945342a0743e209577
Merged-In: I34d9937235c78f18f51b18945342a0743e209577
diff --git a/services/mediaextractor/MediaExtractorService.cpp b/services/mediaextractor/MediaExtractorService.cpp
index 36e084b..ac6b771 100644
--- a/services/mediaextractor/MediaExtractorService.cpp
+++ b/services/mediaextractor/MediaExtractorService.cpp
@@ -20,8 +20,8 @@
 
 #include <utils/Vector.h>
 
+#include <datasource/DataSourceFactory.h>
 #include <media/DataSource.h>
-#include <media/stagefright/DataSourceFactory.h>
 #include <media/stagefright/InterfaceUtils.h>
 #include <media/stagefright/MediaExtractorFactory.h>
 #include <media/stagefright/RemoteDataSource.h>