Use CharacterEncodingDetector in metadataretriever

instead of media scanner. This way the java MediaMetadataRetriever API
will give the same result as the media scanner.
Also apply some tweaks to the encoding detector to improve handling of
ISO-8859-1 tags.

Bug: 16302581, 17205395

Change-Id: I1682a7a6a8bf04cffaa455044ba72dd7fd152d49
diff --git a/media/libmedia/Android.mk b/media/libmedia/Android.mk
index 3be0651..ffadb23 100644
--- a/media/libmedia/Android.mk
+++ b/media/libmedia/Android.mk
@@ -76,9 +76,10 @@
 
 LOCAL_C_INCLUDES := \
     $(TOP)/frameworks/native/include/media/openmax \
+    $(TOP)/frameworks/av/include/media/ \
     $(TOP)/frameworks/av/media/libstagefright \
-    external/icu/icu4c/source/common \
-    external/icu/icu4c/source/i18n \
+    $(TOP)/external/icu/icu4c/source/common \
+    $(TOP)/external/icu/icu4c/source/i18n \
     $(call include-path-for, audio-effects) \
     $(call include-path-for, audio-utils)