RenderTextHarfBuzz: Implement font fallback for Win and Linux

ui/gfx/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/ui.gni")
 
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
 }
@@ skipping 67 matching lines @@
     "color_utils.cc",
     "color_utils.h",
     "display.cc",
     "display.h",
     "display_observer.cc",
     "display_observer.h",
     "favicon_size.cc",
     "favicon_size.h",
     "font.cc",
     "font.h",
+    "font_fallback.h",
+    "font_fallback_linux.cc",
+    "font_fallback_mac.cc",
     "font_fallback_win.cc",
     "font_fallback_win.h",
     "font_list.cc",
     "font_list.h",
     "font_list_impl.cc",
     "font_list_impl.h",
     "font_render_params_android.cc",
     "font_render_params_linux.cc",
     "font_render_params_win.cc",
     "font_render_params.h",
@@ skipping 147 matching lines @@
     if (is_win) {
       sources += [ "render_text_win.cc" ]
     } else if (is_mac) {
       sources += [ "render_text_mac.cc" ]
     } else if (use_pango) {
       sources += [ "render_text_pango.cc" ]
     } else if (use_ozone) {
       sources += [ "render_text_ozone.cc" ]
     }
   }
-  
+
   # iOS.
   if (is_ios) {
     sources -= [
       "codec/jpeg_codec.cc",
       "codec/jpeg_codec.h",
     ]
   } else {
     deps += [ "//third_party:jpeg" ]
   }
 
@@ skipping 147 matching lines @@
 if (is_android) {
   generate_jni("gfx_jni_headers") {
     sources = [
       "../android/java/src/org/chromium/ui/gfx/BitmapHelper.java",
       "../android/java/src/org/chromium/ui/gfx/DeviceDisplayInfo.java",
       "../android/java/src/org/chromium/ui/gfx/ViewConfigurationHelper.java",
     ]
     jni_package = "gfx"
   }
 }