Split AndroidRuntime into AndroidRuntimeBase base-class and the rest.

AndroidRuntimeBase (exported by libandroid_runtime_base.so) is all you need
to link against to gain the ability to do AndroidRuntimeBase::getJNIEnv()
thus minimizing build dependencies.

Change-Id: I2267327ddc0244fc255f4ec2981ac069d30823d1
diff --git a/chromium/Android.mk b/chromium/Android.mk
index bdc5b28..c15ec3d 100644
--- a/chromium/Android.mk
+++ b/chromium/Android.mk
@@ -140,6 +140,7 @@
 
 LOCAL_SHARED_LIBRARIES += \
         libandroid_runtime \
+        libandroid_runtime_derived \
         liblog \
         libcutils \
         libskia \