Remove mediarouter v7 support library from SDK.

Bug: 9425325
Change-Id: Iba64455cf8bcf4892ff9bf10628e7b5272787a1e
diff --git a/core/pathmap.mk b/core/pathmap.mk
index 09f912e..d0339ea 100644
--- a/core/pathmap.mk
+++ b/core/pathmap.mk
@@ -114,7 +114,6 @@
         v4 \
         v7/gridlayout \
         v7/appcompat \
-        v7/mediarouter \
         v8/renderscript \
         v13