Run clang-modernize -use-nullptr over src/extensions/.

extensions/browser/guest_view/guest_view_base.cc

Index: extensions/browser/guest_view/guest_view_base.cc
diff --git a/extensions/browser/guest_view/guest_view_base.cc b/extensions/browser/guest_view/guest_view_base.cc
index a269ecd5773b60141f98c04f59439f2e88b6863d..9e901ace3f2e42b8f3f70cabd886eaeac36bef66 100644
--- a/extensions/browser/guest_view/guest_view_base.cc
+++ b/extensions/browser/guest_view/guest_view_base.cc
@@ -91,7 +91,7 @@ class GuestViewBase::EmbedderWebContentsObserver : public WebContentsObserver {
     if (destroyed_)
       return;
     destroyed_ = true;
-    guest_->embedder_web_contents_ = NULL;
+    guest_->embedder_web_contents_ = nullptr;
     guest_->EmbedderDestroyed();
     guest_->Destroy();
   }
@@ -101,7 +101,7 @@ class GuestViewBase::EmbedderWebContentsObserver : public WebContentsObserver {
 
 GuestViewBase::GuestViewBase(content::BrowserContext* browser_context,
                              int guest_instance_id)
-    : embedder_web_contents_(NULL),
+    : embedder_web_contents_(nullptr),
       embedder_render_process_id_(0),
       browser_context_(browser_context),
       guest_instance_id_(guest_instance_id),
@@ -145,7 +145,7 @@ void GuestViewBase::Init(const std::string& embedder_extension_id,
     // The derived class did not create a WebContents so this class serves no
     // purpose. Let's self-destruct.
     delete this;
-    callback.Run(NULL);
+    callback.Run(nullptr);
     return;
   }
 
@@ -232,7 +232,7 @@ GuestViewBase* GuestViewBase::Create(
       guest_view_registry.Get().find(view_type);
   if (it == guest_view_registry.Get().end()) {
     NOTREACHED();
-    return NULL;
+    return nullptr;
   }
   return it->second.Run(browser_context, guest_instance_id);
 }
@@ -241,7 +241,7 @@ GuestViewBase* GuestViewBase::Create(
 GuestViewBase* GuestViewBase::FromWebContents(WebContents* web_contents) {
   WebContentsGuestViewMap* guest_map = webcontents_guestview_map.Pointer();
   WebContentsGuestViewMap::iterator it = guest_map->find(web_contents);
-  return it == guest_map->end() ? NULL : it->second;
+  return it == guest_map->end() ? nullptr : it->second;
 }
 
 // static
@@ -250,13 +250,13 @@ GuestViewBase* GuestViewBase::From(int embedder_process_id,
   content::RenderProcessHost* host =
       content::RenderProcessHost::FromID(embedder_process_id);
   if (!host)
-    return NULL;
+    return nullptr;
 
   content::WebContents* guest_web_contents =
       GuestViewManager::FromBrowserContext(host->GetBrowserContext())->
           GetGuestByInstanceIDSafely(guest_instance_id, embedder_process_id);
   if (!guest_web_contents)
-    return NULL;
+    return nullptr;
 
   return GuestViewBase::FromWebContents(guest_web_contents);
 }
@@ -478,7 +478,7 @@ void GuestViewBase::CompleteInit(const std::string& embedder_extension_id,
     // The derived class did not create a WebContents so this class serves no
     // purpose. Let's self-destruct.
     delete this;
-    callback.Run(NULL);
+    callback.Run(nullptr);
     return;
   }
   InitWithWebContents(embedder_extension_id,