Add tests for GL_EXT_draw_buffers_indexed.

Add tests for GL_EXT_draw_buffers_indexed extension.

Bug: 18925580
Change-Id: Ia9e3a7a867c5f11a961df4aeaeccc2c5865b58a9
diff --git a/Android.mk b/Android.mk
index 06adb08..e1235d4 100644
--- a/Android.mk
+++ b/Android.mk
@@ -314,6 +314,7 @@
 	modules/gles31/functional/es31fVertexAttributeBindingStateQueryTests.cpp \
 	modules/gles31/functional/es31fVertexAttributeBindingTests.cpp \
 	modules/gles31/functional/es31fCopyImageTests.cpp \
+	modules/gles31/functional/es31fDrawBuffersIndexedTests.cpp \
 	modules/gles31/stress/es31sDrawTests.cpp \
 	modules/gles31/stress/es31sStressTests.cpp \
 	modules/gles31/stress/es31sTessellationGeometryInteractionTests.cpp \