Don't handle the key events with Command (Search) modifier by IME.

chrome/browser/ui/input_method/input_method_engine_base.cc

Index: chrome/browser/ui/input_method/input_method_engine_base.cc
diff --git a/chrome/browser/ui/input_method/input_method_engine_base.cc b/chrome/browser/ui/input_method/input_method_engine_base.cc
index e28670bdfe93bc64990500fe2e833e620ac9c41e..b0301178799de4874a6ac26db2c977cfb6d51e39 100644
--- a/chrome/browser/ui/input_method/input_method_engine_base.cc
+++ b/chrome/browser/ui/input_method/input_method_engine_base.cc
@@ -362,6 +362,11 @@ void InputMethodEngineBase::ProcessKeyEvent(const ui::KeyEvent& key_event,
   // commitText while the extension is handling key event.
   handling_key_event_ = true;
 
+  if (key_event.IsCommandDown()) {
+    callback.Run(false);
+    return;
+  }
+
   KeyboardEvent ext_event;
   GetExtensionKeyboardEventFromKeyEvent(key_event, &ext_event);