Disable proguard to avoid camera crash.

We should check what classes/members we want to keep. Before that, let's disable
it to keep camera working.
diff --git a/Android.mk b/Android.mk
index acd11dc..b11f5cf 100644
--- a/Android.mk
+++ b/Android.mk
@@ -8,6 +8,8 @@
 LOCAL_PACKAGE_NAME := Camera
 LOCAL_CERTIFICATE := media
 
+LOCAL_PROGUARD_ENABLED := disabled
+
 include $(BUILD_PACKAGE)
 
 # Use the following include to make our test apk.