Add new MouseCursor interface for setting the mouse cursor.

ppapi/ppapi_sources.gypi

Index: ppapi/ppapi_sources.gypi
diff --git a/ppapi/ppapi_sources.gypi b/ppapi/ppapi_sources.gypi
index 536f8f3a2a921c8cebe61293c9fe6128ae05f432..553c869623afd726dc2bfa5cdb28ba618e20f247 100644
--- a/ppapi/ppapi_sources.gypi
+++ b/ppapi/ppapi_sources.gypi
@@ -37,6 +37,7 @@
       'c/ppb_input_event.h',
       'c/ppb_instance.h',
       'c/ppb_messaging.h',
+      'c/ppb_mouse_cursor.h',
       'c/ppb_mouse_lock.h',
       'c/ppb_opengles2.h',
       'c/ppb_url_loader.h',
@@ -165,6 +166,8 @@
       'cpp/module.cc',
       'cpp/module.h',
       'cpp/module_impl.h',
+      'cpp/mouse_cursor.cc',
+      'cpp/mouse_cursor.h',
       'cpp/mouse_lock.cc',
       'cpp/mouse_lock.h',
       'cpp/output_traits.h',
@@ -348,6 +351,7 @@
       'tests/test_graphics_2d.cc',
       'tests/test_image_data.cc',
       'tests/test_memory.cc',
+      'tests/test_mouse_cursor.cc',
       'tests/test_paint_aggregator.cc',
       'tests/test_post_message.cc',
       'tests/test_scrollbar.cc',
@@ -413,6 +417,7 @@
       'tests/test_input_event.h',
       'tests/test_memory.cc',
       'tests/test_memory.h',
+      'tests/test_mouse_cursor.cc',
       'tests/test_net_address_private.cc',
       'tests/test_net_address_private.h',
       'tests/test_network_monitor_private.cc',