[Media Controls] Tests for rotate-to-fullscreen meets orientation lock

third_party/WebKit/Source/modules/screen_orientation/ScreenOrientationControllerImpl.cpp

 // 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.
 
 #include "modules/screen_orientation/ScreenOrientationControllerImpl.h"
 
 #include <memory>
 #include <utility>
 #include "core/dom/Document.h"
 #include "core/dom/TaskRunnerHelper.h"
@@ skipping 44 matching lines @@
     const IntRect& rect,
     uint16_t rotation) {
   // Bypass orientation detection in layout tests to get consistent results.
   // FIXME: The screen dimension should be fixed when running the layout tests
   // to avoid such issues.
   if (LayoutTestSupport::IsRunningLayoutTest())
     return kWebScreenOrientationPortraitPrimary;
 
   bool is_tall_display = rotation % 180 ? rect.Height() < rect.Width()
                                         : rect.Height() > rect.Width();
+
+  // https://w3c.github.io/screen-orientation/#dfn-current-orientation-angle
+  // allows the UA to associate *-primary and *-secondary values at will. Blink
+  // arbitrarily chooses rotation 0 to always be portrait-primary or
+  // landscape-primary, and portrait-primary + 90 to be landscape-primary, which
+  // together fully determine the relationship.
   switch (rotation) {
     case 0:
       return is_tall_display ? kWebScreenOrientationPortraitPrimary
                              : kWebScreenOrientationLandscapePrimary;
     case 90:
       return is_tall_display ? kWebScreenOrientationLandscapePrimary
                              : kWebScreenOrientationPortraitSecondary;
     case 180:
       return is_tall_display ? kWebScreenOrientationPortraitSecondary
                              : kWebScreenOrientationLandscapeSecondary;
@@ skipping 162 matching lines @@
 }
 
 DEFINE_TRACE(ScreenOrientationControllerImpl) {
   visitor->Trace(orientation_);
   ContextLifecycleObserver::Trace(visitor);
   Supplement<LocalFrame>::Trace(visitor);
   PlatformEventController::Trace(visitor);
 }
 
 }  // namespace blink