Enable subpixel positioning for internal display with dsf larger than 1.0

ash/display/display_manager_unittest.cc

 // Copyright (c) 2012 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.
 
 #include "ash/display/display_manager.h"
 
+#include "ash/ash_switches.h"
 #include "ash/display/display_controller.h"
 #include "ash/display/display_layout_store.h"
 #include "ash/screen_util.h"
 #include "ash/shell.h"
 #include "ash/test/ash_test_base.h"
 #include "ash/test/display_manager_test_api.h"
 #include "ash/test/mirror_window_test_api.h"
+#include "base/command_line.h"
 #include "base/format_macros.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/stringprintf.h"
 #include "ui/aura/env.h"
 #include "ui/aura/window_observer.h"
 #include "ui/aura/window_tree_host.h"
 #include "ui/events/test/event_generator.h"
 #include "ui/gfx/display.h"
 #include "ui/gfx/display_observer.h"
+#include "ui/gfx/font_render_params.h"
 #include "ui/gfx/screen.h"
 #include "ui/gfx/screen_type_delegate.h"
 
 namespace ash {
 
 using std::vector;
 using std::string;
 
 using base::StringPrintf;
 
@@ skipping 1341 matching lines @@
  private:
   DISALLOW_COPY_AND_ASSIGN(ScreenShutdownTest);
 };
 
 TEST_F(ScreenShutdownTest, ScreenAfterShutdown) {
   if (!SupportsMultipleDisplays())
     return;
   UpdateDisplay("500x300,800x400");
 }
 
+
+#if defined(OS_CHROMEOS)
+template <const char* VALUE, bool INTERNAL>

[Daniel Erat, 2014/08/20 20:14:42]

i thought that there's a general push to avoid templates when possible in
chromium, although i wasn't able to find anything saying this in the style
guide. almost all of the templates that i've seen are used to specialize a class
or function for a given _type_, not to pass values like this code is doing. it
feels tricky and uncommon to me, and i think that using a helper method would be
easier to understand.

[oshima, 2014/08/20 21:54:40]

okay, uploaded new patch. I hope you like it this time!

+class DisplayManagerFontTest : public test::AshTestBase {
+ public:
+  DisplayManagerFontTest() {}
+  virtual ~DisplayManagerFontTest() {}
+
+  virtual void SetUp() OVERRIDE {
+    gfx::ClearFontRenderParamsCacheForTest();
+    base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+    if (INTERNAL)
+      command_line->AppendSwitch(switches::kAshUseFirstDisplayAsInternal);
+    command_line->AppendSwitchASCII(switches::kAshHostWindowBounds, VALUE);
+    test::AshTestBase::SetUp();
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(DisplayManagerFontTest);
+};
+
+const char DSF100[] = "1000x800*1.00";
+const char DSF125[] = "1000x800*1.25";
+const char DSF200[] = "1000x800*2.00";
+typedef DisplayManagerFontTest<DSF100, true> DisplayManagerFontTestInternal100;
+typedef DisplayManagerFontTest<DSF125, true> DisplayManagerFontTestInternal125;
+typedef DisplayManagerFontTest<DSF200, true> DisplayManagerFontTestInternal200;
+
+bool IsTextSubpixelPositioningEnabled() {
+  gfx::FontRenderParams params =
+      gfx::GetFontRenderParams(gfx::FontRenderParamsQuery(false), NULL);
+  return params.subpixel_positioning;
+}
+
+TEST_F(DisplayManagerFontTestInternal100, TestDsf100) {
+  ASSERT_DOUBLE_EQ(1.0f,
+            Shell::GetScreen()->GetPrimaryDisplay().device_scale_factor());
+  EXPECT_FALSE(IsTextSubpixelPositioningEnabled());
+}
+
+TEST_F(DisplayManagerFontTestInternal125, TestDsf125) {
+  ASSERT_DOUBLE_EQ(1.25f,
+            Shell::GetScreen()->GetPrimaryDisplay().device_scale_factor());
+  EXPECT_TRUE(IsTextSubpixelPositioningEnabled());
+}
+
+TEST_F(DisplayManagerFontTestInternal200, TestDsf200) {
+  ASSERT_DOUBLE_EQ(2.0f,
+            Shell::GetScreen()->GetPrimaryDisplay().device_scale_factor());
+  EXPECT_TRUE(IsTextSubpixelPositioningEnabled());
+}
+
+typedef DisplayManagerFontTest<DSF100, false> DisplayManagerFontTestExternal100;
+typedef DisplayManagerFontTest<DSF125, false> DisplayManagerFontTestExternal125;
+typedef DisplayManagerFontTest<DSF200, false> DisplayManagerFontTestExternal200;
+
+TEST_F(DisplayManagerFontTestExternal100, TestDsf100) {
+  ASSERT_DOUBLE_EQ(1.0f,
+            Shell::GetScreen()->GetPrimaryDisplay().device_scale_factor());
+  EXPECT_FALSE(IsTextSubpixelPositioningEnabled());
+}
+
+TEST_F(DisplayManagerFontTestExternal125, TestDsf125) {
+  ASSERT_DOUBLE_EQ(1.25f,
+            Shell::GetScreen()->GetPrimaryDisplay().device_scale_factor());
+  EXPECT_FALSE(IsTextSubpixelPositioningEnabled());
+}
+
+TEST_F(DisplayManagerFontTestExternal200, TestDsf200) {
+  ASSERT_DOUBLE_EQ(2.0f,
+            Shell::GetScreen()->GetPrimaryDisplay().device_scale_factor());
+  EXPECT_FALSE(IsTextSubpixelPositioningEnabled());
+}
+
+#endif  // OS_CHROMEOS
+
 }  // namespace ash