Make PermissionRequest::GetIconId return different types

ui/gfx/vector_icons/microphone.icon

Index: ui/gfx/vector_icons/microphone.icon
diff --git a/ui/gfx/vector_icons/microphone.icon b/ui/gfx/vector_icons/microphone.icon
new file mode 100644
index 0000000000000000000000000000000000000000..8c7962af678b7ab5bd0874e19768b65dfcba9e58
--- /dev/null
+++ b/ui/gfx/vector_icons/microphone.icon
@@ -0,0 +1,24 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+MOVE_TO, 24, 30,
+R_CUBIC_TO, 3.31f, 0, 5.98f, -2.69f, 5.98f, -6,
+LINE_TO, 30, 12,
+R_CUBIC_TO, 0, -3.32f, -2.68f, -6, -6, -6,
+R_CUBIC_TO, -3.31f, 0, -6, 2.68f, -6, 6,
+R_V_LINE_TO, 12,
+R_CUBIC_TO, 0, 3.31f, 2.69f, 6, 6, 6,
+CLOSE,
+R_MOVE_TO, 10.6f, -6,
+R_CUBIC_TO, 0, 6, -5.07f, 10.2f, -10.6f, 10.2f,
+R_CUBIC_TO, -5.52f, 0, -10.6f, -4.2f, -10.6f, -10.2f,
+H_LINE_TO, 10,
+R_CUBIC_TO, 0, 6.83f, 5.44f, 12.47f, 12, 13.44f,
+V_LINE_TO, 44,
+R_H_LINE_TO, 4,
+R_V_LINE_TO, -6.56f,
+R_CUBIC_TO, 6.56f, -0.97f, 12, -6.61f, 12, -13.44f,
+R_H_LINE_TO, -3.4f,
+CLOSE,
+END

[lshang, 2016/10/11 12:26:57]

Why adding a new microphone icon here? What is used for microphone icon on
desktop before this change?

[Evan Stade, 2016/10/12 15:12:36]

a png which is now deleted