Fix potential null pointer access in HTMLMediaElement::seek

third_party/WebKit/Source/core/html/HTMLMediaElementTest.cpp

Index: third_party/WebKit/Source/core/html/HTMLMediaElementTest.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLMediaElementTest.cpp b/third_party/WebKit/Source/core/html/HTMLMediaElementTest.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..9c8f1cd08f9c91dc3f333e1880ceeab4173d2efc
--- /dev/null
+++ b/third_party/WebKit/Source/core/html/HTMLMediaElementTest.cpp
@@ -0,0 +1,54 @@
+// Copyright 2016 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 "core/html/HTMLMediaElement.h"
+
+#include "core/dom/Document.h"
+#include "core/html/HTMLVideoElement.h"
+#include "core/loader/EmptyClients.h"
+#include "core/testing/DummyPageHolder.h"
+#include "platform/testing/UnitTestHelpers.h"
+#include "public/platform/WebMediaPlayer.h"
+#include "public/platform/WebSize.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace blink {
+
+class HTMLMediaElementTest : public ::testing::Test {
+protected:
+    HTMLMediaElementTest()
+        : m_dummyPageHolder(DummyPageHolder::create(IntSize(640, 360), nullptr, EmptyFrameLoaderClient::create()))
+    {
+        m_video = HTMLVideoElement::create(m_dummyPageHolder->document());
+    }
+
+    void breakReadyState()
+    {
+        // Manually setup a situation when ready state goes out of sync with
+        // m_webMediaPlayer. The real call sequence that results in error is unkown.
+        m_video->setPreload("none");
+        m_video->setSrc("http://foo.bar/");
+        testing::runPendingTasks();
+        m_video->setReadyState(HTMLMediaElement::HAVE_FUTURE_DATA);
+        m_video->remoteRouteAvailabilityChanged(true);

[mlamouri (slow - plz ping), 2016/05/19 13:13:03]

Do you really need this line?

+    }
+
+    OwnPtr<DummyPageHolder> m_dummyPageHolder;
+    Persistent<HTMLVideoElement> m_video;
+};
+
+TEST_F(HTMLMediaElementTest, webMediaPlayerOutOfSyncWithReadyState)
+{
+    breakReadyState();
+
+    WebMediaPlayer* player = m_video->webMediaPlayer();
+    ASSERT_FALSE(player);
+
+    // Call setCurrentTime that accesses m_webMediaPlayer
+    // If a check of m_webMediaPlayer for nullptr is missing,
+    // the test crashes.
+    m_video->setCurrentTime(0.0);
+}
+
+} // namespace blink