Add flag to enable immersive fullscreen for v2 apps

apps/app_window_contents.cc

Index: apps/app_window_contents.cc
diff --git a/apps/app_window_contents.cc b/apps/app_window_contents.cc
index 751ccc2d3535152d0e65a6e01c14455e372bb777..1b6dcdd7f1739267b0af13a6a020f929698bac4b 100644
--- a/apps/app_window_contents.cc
+++ b/apps/app_window_contents.cc
@@ -94,11 +94,26 @@ void AppWindowContents::NativeWindowChanged(
   update.width.reset(new int(bounds.width()));
   update.height.reset(new int(bounds.height()));
   dictionary->Set("bounds", update.ToValue().release());
-  dictionary->SetBoolean("fullscreen",
-                         native_app_window->IsFullscreenOrPending());
-  dictionary->SetBoolean("minimized", native_app_window->IsMinimized());
-  dictionary->SetBoolean("maximized", native_app_window->IsMaximized());
   dictionary->SetBoolean("alwaysOnTop", native_app_window->IsAlwaysOnTop());
+  dictionary->SetBoolean("minimized", native_app_window->IsMinimized());
+
+  bool maximized = native_app_window->IsMaximized();
+  ShellWindow::FullscreenType fullscreen_type = host_->fullscreen_type();
+  // Check both the fullscreen type and |native_app_window| so that the window
+  // is reported as fullscreen if the fullscreen state lags behind that of
+  // ShellWindow. (This is the case in the GTK port).
+  bool fullscreen = (fullscreen_type != ShellWindow::FULLSCREEN_TYPE_NONE) ||
+      native_app_window->IsFullscreen();
+  if (fullscreen_type == ShellWindow::FULLSCREEN_TYPE_IMMERSIVE) {
+    // A window in immersive fullscreen on ChromeOS does not take up all of the
+    // pixels on screen because the shelf is auto hidden, not completely hidden.
+    // For this reason, immersive fullscreen windows are considered maximized
+    // for the sake of the app.window api.
+    fullscreen = false;
+    maximized = true;
+  }
+  dictionary->SetBoolean("fullscreen", fullscreen);
+  dictionary->SetBoolean("maximized", maximized);
 
   const ShellWindow::SizeConstraints& size_constraints =
       host_->size_constraints();