Implement GetTextFromRange(), GetTextRange() and GetSelectionRange() for ArcImeService.

components/arc/common/ime.typemap

Index: components/arc/common/ime.typemap
diff --git a/components/arc/common/ime.typemap b/components/arc/common/ime.typemap
new file mode 100644
index 0000000000000000000000000000000000000000..141f4ad18ce78abe8e559bc7d75b0787d174ac5f
--- /dev/null
+++ b/components/arc/common/ime.typemap
@@ -0,0 +1,20 @@
+# Copyright 2017 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+mojom = "//components/arc/common/ime.mojom"
+public_headers = [
+  "//ui/gfx/geometry/rect.h",
+  "//ui/gfx/range/range.h",
+]
+deps = [
+  "//ui/gfx",
+]
+traits_headers = [ "//components/arc/ime/arc_ime_struct_traits.h" ]
+sources = [
+  "//components/arc/ime/arc_ime_struct_traits.cc",
+]
+type_mappings = [
+  "arc.mojom.CursorRect=::gfx::Rect[move_only]",
+  "arc.mojom.TextRange=::gfx::Range[move_only]",
+]