Merge commit '3a74ee528255cc027d84b204a87b5c25e47bff79'

Merged from upstream:
    https://github.com/harfbuzz/harfbuzz.git refs/tags/2.6.4

Also update `Android.bp`.

NO_TYPO_CHECK=true

Change-Id: I606b1dc9a4994b2fb110a66309a57b00ec85da09
diff --git a/Android.bp b/Android.bp
index 95d9b70..9f29062 100644
--- a/Android.bp
+++ b/Android.bp
@@ -67,8 +67,10 @@
         "src/hb-buffer.cc",
         "src/hb-common.cc",
         "src/hb-face.cc",
+        "src/hb-fallback-shape.cc",
         "src/hb-font.cc",
         "src/hb-icu.cc",
+        "src/hb-number.cc",
         "src/hb-ot-cff1-table.cc",
         "src/hb-ot-cff2-table.cc",
         "src/hb-ot-face.cc",
@@ -76,6 +78,7 @@
         "src/hb-ot-layout.cc",
         "src/hb-ot-map.cc",
         "src/hb-ot-math.cc",
+        "src/hb-ot-metrics.cc",
         "src/hb-ot-shape-complex-arabic.cc",
         "src/hb-ot-shape-complex-default.cc",
         "src/hb-ot-shape-complex-hangul.cc",
@@ -98,8 +101,8 @@
         "src/hb-shape.cc",
         "src/hb-shaper.cc",
         "src/hb-static.cc",
+        "src/hb-ucd.cc",
         "src/hb-unicode.cc",
-        "src/hb-warning.cc",
     ],
 
     target: {