Make GL build script compatible with jb (and mr1.1, mr2)

Notice that in jb, the GL encoder is located in sdk/emulator/opengl. In
jb-mr1.1, the encoder is in development/tools/emulator/opengl.

After this patch, it should just work if you copy the opengl directory
from mnc to jb.

Change-Id: I4b6ba6daeb64315ecf72b52b142acbbccdc4dbe0
diff --git a/common.mk b/common.mk
index 4500a70..1f04fb1 100644
--- a/common.mk
+++ b/common.mk
@@ -41,6 +41,10 @@
 ifeq ($(shell test $(PLATFORM_SDK_VERSION) -lt 23 && echo PreMarshmallow),PreMarshmallow)
     emugl-begin-module += $(eval include external/stlport/libstlport.mk)
 endif
+ifeq ($(shell test $(PLATFORM_SDK_VERSION) -lt 19 && echo PreKitkat),PreKitkat)
+    emugl-begin-module += $(eval LOCAL_MODULE_TAGS := debug)
+    emugl-begin-module += $(eval LOCAL_SHARED_LIBRARIES += libstlport)
+endif
 
 ifeq ($(shell test $(PLATFORM_SDK_VERSION) -lt 21 && echo PreLollipop),PreLollipop)
     emugl-begin-module += $(eval LOCAL_PRELINK_MODULE := false)