Add TRACE_EVENT markers to various keyboard functions

ui/keyboard/keyboard_layout_manager.cc

Index: ui/keyboard/keyboard_layout_manager.cc
diff --git a/ui/keyboard/keyboard_layout_manager.cc b/ui/keyboard/keyboard_layout_manager.cc
index 178a86461a896ea33c9e236c2e82a9ee444918d6..3efe6df2360857aa5216a47101a7458b0ccbd88c 100644
--- a/ui/keyboard/keyboard_layout_manager.cc
+++ b/ui/keyboard/keyboard_layout_manager.cc
@@ -44,6 +44,8 @@ void KeyboardLayoutManager::SetChildBounds(aura::Window* child,
                                            const gfx::Rect& requested_bounds) {
   DCHECK(child == keyboard_);
 
+  TRACE_EVENT0("vk", "KeyboardLayoutSetChildBounds");
+
   // Request to change the bounds of child window (AKA the virtual keyboard
   // window) should change the container window first. Then the child window is
   // resized and covers the container window. Note the child's bound is only set