Reland of Android: support multiple displays on C++ side

ui/android/display_android_manager.cc

+// Copyright 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 "ui/android/display_android_manager.h"
+
+#include <jni.h>
+#include <map>
+
+#include "base/android/jni_android.h"
+#include "base/stl_util.h"
+#include "jni/DisplayAndroidManager_jni.h"
+#include "ui/android/screen_android.h"
+#include "ui/android/window_android.h"
+#include "ui/display/display.h"
+
+namespace ui {
+
+using base::android::AttachCurrentThread;
+using display::Display;
+using display::DisplayObserver;
+
+void SetScreenAndroid() {
+  // Do not override existing Screen.
+  if (display::Screen::GetScreen())

[boliu, 2016/11/14 15:48:53]

this should be a DCHECK (or if you feel unsafe, a CHECK), it should not be a run
time check that just swallows the error

[Tima Vaisburd, 2016/11/14 20:11:08]

I think DCHECK is better. Replaced with DCHECK.

+    return;
+
+  DisplayAndroidManager* manager = new DisplayAndroidManager();
+  display::Screen::SetScreenInstance(manager);
+
+  JNIEnv* env = AttachCurrentThread();
+  Java_DisplayAndroidManager_onNativeSideCreated(env, (jlong)manager);
+}
+
+bool RegisterScreenAndroid(JNIEnv* env) {
+  return RegisterNativesImpl(env);
+}
+
+DisplayAndroidManager::DisplayAndroidManager() {}
+
+DisplayAndroidManager::~DisplayAndroidManager() {}
+
+// Screen interface.
+
+gfx::Point DisplayAndroidManager::GetCursorScreenPoint() {
+  NOTIMPLEMENTED();
+  return gfx::Point();
+}
+
+bool DisplayAndroidManager::IsWindowUnderCursor(gfx::NativeWindow window) {
+  NOTIMPLEMENTED();
+  return false;
+}
+
+gfx::NativeWindow DisplayAndroidManager::GetWindowAtScreenPoint(
+    const gfx::Point& point) {
+  NOTIMPLEMENTED();
+  return NULL;
+}
+
+int DisplayAndroidManager::GetNumDisplays() const {
+  DCHECK_GE(displays_.size(), 1U);
+  return displays_.size();
+}
+
+std::vector<Display> DisplayAndroidManager::GetAllDisplays() const {
+  DCHECK_GE(displays_.size(), 1U);
+
+  std::vector<Display> result;
+  for (const auto& display : displays_)
+    result.push_back(display.second);
+
+  return result;
+}
+
+Display DisplayAndroidManager::GetDisplayNearestWindow(
+    gfx::NativeView view) const {
+  ui::WindowAndroid* window = view ? view->GetWindowAndroid() : nullptr;
+  if (window) {
+    DisplayMap::const_iterator it = displays_.find(window->display_id());
+    if (it != displays_.end()) {
+      return it->second;
+    }
+  }
+  return GetPrimaryDisplay();
+}
+
+Display DisplayAndroidManager::GetDisplayNearestPoint(
+    const gfx::Point& point) const {
+  NOTIMPLEMENTED();
+  return GetPrimaryDisplay();
+}
+
+Display DisplayAndroidManager::GetDisplayMatching(
+    const gfx::Rect& match_rect) const {
+  NOTIMPLEMENTED();
+  return GetPrimaryDisplay();
+}
+
+Display DisplayAndroidManager::GetPrimaryDisplay() const {
+  DisplayMap::const_iterator it = displays_.find(primary_display_id_);
+  // Primary display must be set before the first call to this method.
+  CHECK(it != displays_.end());
+  return it->second;
+}
+
+void DisplayAndroidManager::AddObserver(DisplayObserver* observer) {
+  NOTIMPLEMENTED();
+}
+
+void DisplayAndroidManager::RemoveObserver(DisplayObserver* observer) {
+  NOTIMPLEMENTED();
+}
+
+// Methods called from Java
+
+void DisplayAndroidManager::UpdateDisplay(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& jobject,
+    jint sdkDisplayId,
+    jint physicalWidth,
+    jint physicalHeight,
+    jint width,
+    jint height,
+    jfloat dipScale,
+    jint rotationDegrees,
+    jint bitsPerPixel,
+    jint bitsPerComponent) {
+  gfx::Rect bounds_in_pixels = gfx::Rect(physicalWidth, physicalHeight);
+
+  // Physical width and height might be not supported.
+  if (bounds_in_pixels.IsEmpty())
+    bounds_in_pixels = gfx::Rect(width, height);
+
+  const gfx::Rect bounds_in_dip = gfx::Rect(
+      gfx::ScaleToCeiledSize(bounds_in_pixels.size(), 1.0f / dipScale));
+
+  display::Display display(sdkDisplayId, bounds_in_dip);
+
+  display.set_device_scale_factor(dipScale);
+  display.SetRotationAsDegree(rotationDegrees);
+  display.set_color_depth(bitsPerPixel);
+  display.set_depth_per_component(bitsPerComponent);
+  display.set_is_monochrome(bitsPerComponent == 0);
+
+  displays_[sdkDisplayId] = display;
+}
+
+void DisplayAndroidManager::RemoveDisplay(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& jobject,
+    jint sdkDisplayId) {
+  displays_.erase(sdkDisplayId);
+}
+
+void DisplayAndroidManager::SetPrimaryDisplayId(
+    JNIEnv* env,
+    const base::android::JavaParamRef<jobject>& jobject,
+    jint sdkDisplayId) {
+  primary_display_id_ = sdkDisplayId;
+}
+
+}  // namespace ui