Use the physical-pixel space for native IME on linux platform.

components/arc/ime/arc_ime_service.cc

Index: components/arc/ime/arc_ime_service.cc
diff --git a/components/arc/ime/arc_ime_service.cc b/components/arc/ime/arc_ime_service.cc
index 7d49a17b62e620413ffb0302d60c0d144ab9c47f..d287adde2c3034be1b45553205143dc4481b3b25 100644
--- a/components/arc/ime/arc_ime_service.cc
+++ b/components/arc/ime/arc_ime_service.cc
@@ -273,6 +273,10 @@ ui::TextInputType ArcImeService::GetTextInputType() const {
   return ime_type_;
 }
 
+float ArcImeService::GetScaleFactor() const {
+  return 1.0f;

[Shu Chen, 2016/12/22 01:12:23]

There might be a TODO for this.

+}
+
 gfx::Rect ArcImeService::GetCaretBounds() const {
   if (focused_arc_window_.windows().empty())
     return gfx::Rect();