Wrap tintable icons with correctly tinted drawable XML

Replaces pre-tinted icons with flat black, grayscale versions suitable
for use as alpha masks.

Bug: 20143927
Change-Id: I0bca5dee6fcb273902db174c818cc529a5c13f91

wrap_alpha.py

@@ -0,0 +1,43 @@
+#!/usr/bin/python
+
+import os
+
+# assume everything needs alpha suffixes
+for root, dirs, files in os.walk('.'):
+    if "res/drawable-" not in root: continue
+
+    for before in files:
+        if "_alpha.png" in before: continue
+        if not before.startswith("ic_settings_"): continue
+
+        after = before.replace(".png", "_alpha.png")
+        os.rename(os.path.join(root, before), os.path.join(root, after))
+
+# build xml redirection
+for root, dirs, files in os.walk('.'):
+    if "res/drawable-" not in root: continue
+
+    for src in files:
+        if not src.endswith(".png"): continue
+        src = src[0:-4]
+
+        src_clause = '\n    android:src="@drawable/%s"' % (src)
+
+        alpha = src.endswith("_alpha")
+        if alpha:
+            src = src[0:-6]
+            alpha_clause = '\n    android:tint="?android:attr/colorAccent"'
+        else:
+            alpha_clause = ''
+
+        am = src.endswith("_am")
+        if am:
+            src = src[0:-3]
+            am_clause = '\n    android:autoMirrored="true"'
+        else:
+            am_clause = ''
+
+        with open("res/drawable/%s.xml" % (src), 'w') as xml:
+            xml.write("""<?xml version="1.0" encoding="utf-8"?>
+<bitmap xmlns:android="http://schemas.android.com/apk/res/android"%s%s%s />
+""" % (src_clause, alpha_clause, am_clause))