Make FrameDestructionObserver::m_frame a private.

Source/core/plugins/DOMMimeTypeArray.cpp

Index: Source/core/plugins/DOMMimeTypeArray.cpp
diff --git a/Source/core/plugins/DOMMimeTypeArray.cpp b/Source/core/plugins/DOMMimeTypeArray.cpp
index 3410fdba2384325eaf351c5cd279bb8c76a6e309..32904c922aea436dd54f8853d8982d2a1062eaa9 100644
--- a/Source/core/plugins/DOMMimeTypeArray.cpp
+++ b/Source/core/plugins/DOMMimeTypeArray.cpp
@@ -54,14 +54,14 @@ PassRefPtrWillBeRawPtr<DOMMimeType> DOMMimeTypeArray::item(unsigned index)
     const Vector<MimeClassInfo>& mimes = data->mimes();
     if (index >= mimes.size())
         return nullptr;
-    return DOMMimeType::create(data, m_frame, index).get();
+    return DOMMimeType::create(data, m_frame, index);
 }
 
 bool DOMMimeTypeArray::canGetItemsForName(const AtomicString& propertyName)
 {
     PluginData *data = getPluginData();
     if (!data)
-        return 0;
+        return false;
     const Vector<MimeClassInfo>& mimes = data->mimes();
     for (unsigned i = 0; i < mimes.size(); ++i) {
         if (mimes[i].type == propertyName)
@@ -78,7 +78,7 @@ PassRefPtrWillBeRawPtr<DOMMimeType> DOMMimeTypeArray::namedItem(const AtomicStri
     const Vector<MimeClassInfo>& mimes = data->mimes();
     for (unsigned i = 0; i < mimes.size(); ++i) {
         if (mimes[i].type == propertyName)
-            return DOMMimeType::create(data, m_frame, i).get();
+            return DOMMimeType::create(data, m_frame, i);
     }
     return nullptr;
 }
@@ -86,10 +86,10 @@ PassRefPtrWillBeRawPtr<DOMMimeType> DOMMimeTypeArray::namedItem(const AtomicStri
 PluginData* DOMMimeTypeArray::getPluginData() const
 {
     if (!m_frame)
-        return 0;
+        return nullptr;
     Page* p = m_frame->page();
     if (!p)
-        return 0;
+        return nullptr;
     return p->pluginData();
 }