Add enum converter.

Converts between two different enumerations.

BUG: 30140438
TEST: Unit tests pass
Change-Id: I0976c440f0a48491fa52d26e173808917d53ebe7
diff --git a/modules/camera/3_4/Android.mk b/modules/camera/3_4/Android.mk
index 278a351..4c77968 100644
--- a/modules/camera/3_4/Android.mk
+++ b/modules/camera/3_4/Android.mk
@@ -39,6 +39,7 @@
 
 v4l2_src_files := \
   camera.cpp \
+  metadata/enum_converter.cpp \
   metadata/metadata.cpp \
   metadata/v4l2_enum_control.cpp \
   stream.cpp \
@@ -51,6 +52,7 @@
 
 v4l2_test_files := \
   metadata/control_test.cpp \
+  metadata/enum_converter_test.cpp \
   metadata/fixed_property_test.cpp \
   metadata/ignored_control_test.cpp \
   metadata/metadata_test.cpp \