Add the partial screen magnifier to Chrome OS.

ash/ash.gyp

Index: ash/ash.gyp
diff --git a/ash/ash.gyp b/ash/ash.gyp
index a766593b0f89e6c16bcef746272d3cf6f62a401f..3f3a4caeed9239d5a507a871c5c7ab7f984d7893 100644
--- a/ash/ash.gyp
+++ b/ash/ash.gyp
@@ -99,6 +99,10 @@
         'focus_cycler.h',
         'high_contrast/high_contrast_controller.cc',
         'high_contrast/high_contrast_controller.h',
+        'keyboard_overlay/keyboard_overlay_delegate.cc',
+        'keyboard_overlay/keyboard_overlay_delegate.h',
+        'keyboard_overlay/keyboard_overlay_view.cc',
+        'keyboard_overlay/keyboard_overlay_view.h',
         'launcher/app_list_button.cc',
         'launcher/app_list_button.h',
         'launcher/background_animator.cc',
@@ -130,10 +134,8 @@
         'launcher/tabbed_launcher_button.h',
         'magnifier/magnification_controller.cc',
         'magnifier/magnification_controller.h',
-        'keyboard_overlay/keyboard_overlay_delegate.cc',
-        'keyboard_overlay/keyboard_overlay_delegate.h',
-        'keyboard_overlay/keyboard_overlay_view.cc',
-        'keyboard_overlay/keyboard_overlay_view.h',
+        'magnifier/partial_magnification_controller.cc',
+        'magnifier/partial_magnification_controller.h',
         'root_window_controller.cc',
         'root_window_controller.h',
         'rotator/screen_rotation.cc',