Add missing xxxhdpi icon, remove redundant icons.

- ic_overflow_menu. This is provided already by PhoneCommon.
+ add xxxhdpi asset for ic_arrow_back (black).

Bug: 18300861
Change-Id: I535e9be8ff4177574b922e55649ae820cc9f7d87
diff --git a/res/drawable-hdpi/ic_overflow_menu.png b/res/drawable-hdpi/ic_overflow_menu.png
deleted file mode 100644
index 262e9df..0000000
--- a/res/drawable-hdpi/ic_overflow_menu.png
+++ /dev/null
Binary files differ
diff --git a/res/drawable-mdpi/ic_overflow_menu.png b/res/drawable-mdpi/ic_overflow_menu.png
deleted file mode 100644
index 0e720dd..0000000
--- a/res/drawable-mdpi/ic_overflow_menu.png
+++ /dev/null
Binary files differ
diff --git a/res/drawable-xhdpi/ic_overflow_menu.png b/res/drawable-xhdpi/ic_overflow_menu.png
deleted file mode 100644
index 9156076..0000000
--- a/res/drawable-xhdpi/ic_overflow_menu.png
+++ /dev/null
Binary files differ
diff --git a/res/drawable-xxhdpi/ic_overflow_menu.png b/res/drawable-xxhdpi/ic_overflow_menu.png
deleted file mode 100644
index 92526f5..0000000
--- a/res/drawable-xxhdpi/ic_overflow_menu.png
+++ /dev/null
Binary files differ
diff --git a/res/drawable-xxxhdpi/ic_arrow_back_24dp.png b/res/drawable-xxxhdpi/ic_arrow_back_24dp.png
new file mode 100644
index 0000000..037b6f1
--- /dev/null
+++ b/res/drawable-xxxhdpi/ic_arrow_back_24dp.png
Binary files differ