Revert 224473 "Remove dependency on ui::ScaleFactor from ui/gfx"

trunk/src/ui/base/layout.cc

Index: trunk/src/ui/base/layout.cc
===================================================================
--- trunk/src/ui/base/layout.cc	(revision 224498)
+++ trunk/src/ui/base/layout.cc	(working copy)
@@ -15,24 +15,30 @@
 #include "ui/base/touch/touch_device.h"
 #include "ui/base/ui_base_switches.h"
 #include "ui/gfx/display.h"
-#include "ui/gfx/image/image_skia.h"
 #include "ui/gfx/screen.h"
 
+#if defined(OS_MACOSX) && !defined(OS_IOS)
+#include "base/mac/mac_util.h"
+#endif
+
 #if defined(OS_WIN)
 #include "base/win/metro.h"
+#include "ui/gfx/win/dpi.h"
 #include <Windows.h>
 #endif  // defined(OS_WIN)
 
+#if defined(OS_CHROMEOS)
+#include "ui/base/resource/resource_bundle.h"
+#endif
+
 namespace ui {
 
 namespace {
 
 bool ScaleFactorComparator(const ScaleFactor& lhs, const ScaleFactor& rhs){
-  return GetImageScale(lhs) < GetImageScale(rhs);
+  return GetScaleFactorScale(lhs) < GetScaleFactorScale(rhs);
 }
 
-std::vector<ScaleFactor>* g_supported_scale_factors = NULL;
-
 #if defined(OS_WIN)
 // Helper function that determines whether we want to optimize the UI for touch.
 bool UseTouchOptimizedUI() {
@@ -66,8 +72,75 @@
                kScaleFactorScales_incorrect_size);
 const size_t kScaleFactorScalesLength = arraysize(kScaleFactorScales);
 
+namespace {
+
+// Returns the scale factor closest to |scale| from the full list of factors.
+// Note that it does NOT rely on the list of supported scale factors.
+// Finding the closest match is inefficient and shouldn't be done frequently.
+ScaleFactor FindClosestScaleFactorUnsafe(float scale) {
+  float smallest_diff =  std::numeric_limits<float>::max();
+  ScaleFactor closest_match = SCALE_FACTOR_100P;
+  for (int i = SCALE_FACTOR_100P; i < NUM_SCALE_FACTORS; ++i) {
+    const ScaleFactor scale_factor = static_cast<ScaleFactor>(i);
+    float diff = std::abs(kScaleFactorScales[scale_factor] - scale);
+    if (diff < smallest_diff) {
+      closest_match = scale_factor;
+      smallest_diff = diff;
+    }
+  }
+  return closest_match;
+}
+
 }  // namespace
 
+std::vector<ScaleFactor>& GetSupportedScaleFactorsInternal() {
+  static std::vector<ScaleFactor>* supported_scale_factors =
+      new std::vector<ScaleFactor>();
+  if (supported_scale_factors->empty()) {
+#if !defined(OS_IOS)
+    // On platforms other than iOS, 100P is always a supported scale factor.
+    supported_scale_factors->push_back(SCALE_FACTOR_100P);
+#endif
+
+#if defined(OS_ANDROID)
+    const gfx::Display display =
+        gfx::Screen::GetNativeScreen()->GetPrimaryDisplay();
+    const float display_density = display.device_scale_factor();
+    const ScaleFactor closest = FindClosestScaleFactorUnsafe(display_density);
+    if (closest != SCALE_FACTOR_100P)
+      supported_scale_factors->push_back(closest);
+#elif defined(OS_IOS)
+    gfx::Display display = gfx::Screen::GetNativeScreen()->GetPrimaryDisplay();
+    if (display.device_scale_factor() > 1.0) {
+      DCHECK_EQ(2.0, display.device_scale_factor());
+      supported_scale_factors->push_back(SCALE_FACTOR_200P);
+    } else {
+      supported_scale_factors->push_back(SCALE_FACTOR_100P);
+    }
+#elif defined(OS_MACOSX)
+    if (base::mac::IsOSLionOrLater())
+      supported_scale_factors->push_back(SCALE_FACTOR_200P);
+#elif defined(OS_WIN)
+    // Have high-DPI resources for 140% and 180% scaling on Windows based on
+    // default scaling for Metro mode.  Round to nearest supported scale in
+    // all cases.
+    if (gfx::IsInHighDPIMode()) {
+      supported_scale_factors->push_back(SCALE_FACTOR_140P);
+      supported_scale_factors->push_back(SCALE_FACTOR_180P);
+    }
+#elif defined(OS_CHROMEOS)
+    // TODO(oshima): Include 200P only if the device support 200P
+    supported_scale_factors->push_back(SCALE_FACTOR_200P);
+#endif
+    std::sort(supported_scale_factors->begin(),
+              supported_scale_factors->end(),
+              ScaleFactorComparator);
+  }
+  return *supported_scale_factors;
+}
+
+}  // namespace
+
 DisplayLayout GetDisplayLayout() {
 #if defined(OS_WIN)
   if (UseTouchOptimizedUI())
@@ -76,37 +149,13 @@
   return LAYOUT_DESKTOP;
 }
 
-void SetSupportedScaleFactors(
-    const std::vector<ui::ScaleFactor>& scale_factors) {
-  if (g_supported_scale_factors != NULL)
-    delete g_supported_scale_factors;
-
-  g_supported_scale_factors = new std::vector<ScaleFactor>(scale_factors);
-  std::sort(g_supported_scale_factors->begin(),
-            g_supported_scale_factors->end(),
-            ScaleFactorComparator);
-
-  // Set ImageSkia's supported scales.
-  std::vector<float> scales;
-  for (std::vector<ScaleFactor>::const_iterator it =
-          g_supported_scale_factors->begin();
-       it != g_supported_scale_factors->end(); ++it) {
-    scales.push_back(GetImageScale(*it));
-  }
-  gfx::ImageSkia::SetSupportedScales(scales);
-}
-
-const std::vector<ScaleFactor>& GetSupportedScaleFactors() {
-  DCHECK(g_supported_scale_factors != NULL);
-  return *g_supported_scale_factors;
-}
-
-ScaleFactor GetSupportedScaleFactor(float scale) {
-  DCHECK(g_supported_scale_factors != NULL);
+ScaleFactor GetScaleFactorFromScale(float scale) {
   ScaleFactor closest_match = SCALE_FACTOR_100P;
   float smallest_diff =  std::numeric_limits<float>::max();
-  for (size_t i = 0; i < g_supported_scale_factors->size(); ++i) {
-    ScaleFactor scale_factor = (*g_supported_scale_factors)[i];
+  const std::vector<ScaleFactor>& supported =
+      GetSupportedScaleFactorsInternal();
+  for (size_t i = 0; i < supported.size(); ++i) {
+    ScaleFactor scale_factor = supported[i];
     float diff = std::abs(kScaleFactorScales[scale_factor] - scale);
     if (diff < smallest_diff) {
       closest_match = scale_factor;
@@ -117,55 +166,49 @@
   return closest_match;
 }
 
-float GetImageScale(ScaleFactor scale_factor) {
+float GetScaleFactorScale(ScaleFactor scale_factor) {
   return kScaleFactorScales[scale_factor];
 }
 
-bool IsScaleFactorSupported(ScaleFactor scale_factor) {
-  DCHECK(g_supported_scale_factors != NULL);
-  return std::find(g_supported_scale_factors->begin(),
-                   g_supported_scale_factors->end(),
-                   scale_factor) != g_supported_scale_factors->end();
+ScaleFactor GetMaxScaleFactor() {
+#if defined(OS_CHROMEOS)
+  return ResourceBundle::GetSharedInstance().max_scale_factor();
+#else
+  return GetSupportedScaleFactorsInternal().back();
+#endif
 }
 
-// Returns the scale factor closest to |scale| from the full list of factors.
-// Note that it does NOT rely on the list of supported scale factors.
-// Finding the closest match is inefficient and shouldn't be done frequently.
-ScaleFactor FindClosestScaleFactorUnsafe(float scale) {
-  float smallest_diff =  std::numeric_limits<float>::max();
-  ScaleFactor closest_match = SCALE_FACTOR_100P;
-  for (int i = SCALE_FACTOR_100P; i < NUM_SCALE_FACTORS; ++i) {
-    const ScaleFactor scale_factor = static_cast<ScaleFactor>(i);
-    float diff = std::abs(kScaleFactorScales[scale_factor] - scale);
-    if (diff < smallest_diff) {
-      closest_match = scale_factor;
-      smallest_diff = diff;
-    }
-  }
-  return closest_match;
+std::vector<ScaleFactor> GetSupportedScaleFactors() {
+  return GetSupportedScaleFactorsInternal();
 }
 
+bool IsScaleFactorSupported(ScaleFactor scale_factor) {
+  const std::vector<ScaleFactor>& supported =
+      GetSupportedScaleFactorsInternal();
+  return std::find(supported.begin(), supported.end(), scale_factor) !=
+      supported.end();
+}
+
 namespace test {
 
+void SetSupportedScaleFactors(
+    const std::vector<ui::ScaleFactor>& scale_factors) {
+  std::vector<ui::ScaleFactor>& supported_scale_factors =
+      GetSupportedScaleFactorsInternal();
+  supported_scale_factors = scale_factors;
+  std::sort(supported_scale_factors.begin(),
+            supported_scale_factors.end(),
+            ScaleFactorComparator);
+}
+
 ScopedSetSupportedScaleFactors::ScopedSetSupportedScaleFactors(
-    const std::vector<ui::ScaleFactor>& new_scale_factors) {
-  if (g_supported_scale_factors) {
-    original_scale_factors_ =
-        new std::vector<ScaleFactor>(*g_supported_scale_factors);
-  } else {
-    original_scale_factors_ = NULL;
-  }
+    const std::vector<ui::ScaleFactor>& new_scale_factors)
+    : original_scale_factors_(GetSupportedScaleFactors()) {
   SetSupportedScaleFactors(new_scale_factors);
 }
 
 ScopedSetSupportedScaleFactors::~ScopedSetSupportedScaleFactors() {
-  if (original_scale_factors_) {
-    SetSupportedScaleFactors(*original_scale_factors_);
-    delete original_scale_factors_;
-  } else {
-    delete g_supported_scale_factors;
-    g_supported_scale_factors = NULL;
-  }
+  SetSupportedScaleFactors(original_scale_factors_);
 }
 
 }  // namespace test
@@ -175,7 +218,7 @@
   gfx::Screen* screen = gfx::Screen::GetScreenFor(view);
   if (screen->IsDIPEnabled()) {
     gfx::Display display = screen->GetDisplayNearestWindow(view);
-    return GetSupportedScaleFactor(display.device_scale_factor());
+    return GetScaleFactorFromScale(display.device_scale_factor());
   }
   return ui::SCALE_FACTOR_100P;
 }