Miscellaneous cleanups from several months ago I never got around to landing.

chrome/browser/download/download_request_limiter.cc

 // Copyright (c) 2012 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 "chrome/browser/download/download_request_limiter.h"
 
 #include "base/bind.h"
 #include "base/stl_util.h"
 #include "chrome/browser/download/download_request_infobar_delegate.h"
 #include "chrome/browser/infobars/infobar_tab_helper.h"
@@ skipping 110 matching lines @@
     : host_(NULL),
       status_(DownloadRequestLimiter::ALLOW_ONE_DOWNLOAD),
       download_count_(0),
       infobar_(NULL) {
 }
 
 void DownloadRequestLimiter::TabDownloadState::Observe(
     int type,
     const content::NotificationSource& source,
     const content::NotificationDetails& details) {
-  if (type != content::NOTIFICATION_NAV_ENTRY_PENDING &&
-      type != content::NOTIFICATION_WEB_CONTENTS_DESTROYED) {
-    NOTREACHED();
-    return;
-  }
   content::NavigationController* controller = &web_contents()->GetController();
-  if (type == content::NOTIFICATION_NAV_ENTRY_PENDING &&
-      content::Source<NavigationController>(source).ptr() != controller) {
-    NOTREACHED();
-    return;
-  }
-  if (type == content::NOTIFICATION_WEB_CONTENTS_DESTROYED &&
-      &content::Source<content::WebContents>(source).ptr()->
-          GetController() != controller) {
-    NOTREACHED();
-    return;
-  }
+  if (type == content::NOTIFICATION_NAV_ENTRY_PENDING) {
+    DCHECK_EQ(controller, content::Source<NavigationController>(source).ptr());
 
-  switch (type) {
-    case content::NOTIFICATION_NAV_ENTRY_PENDING: {
-      // NOTE: resetting state on a pending navigate isn't ideal. In particular
-      // it is possible that queued up downloads for the page before the
-      // pending navigate will be delivered to us after we process this
-      // request. If this happens we may let a download through that we
-      // shouldn't have. But this is rather rare, and it is difficult to get
-      // 100% right, so we don't deal with it.
-      NavigationEntry* entry = controller->GetPendingEntry();
-      if (!entry)
+    // NOTE: Resetting state on a pending navigate isn't ideal. In particular it
+    // is possible that queued up downloads for the page before the pending
+    // navigation will be delivered to us after we process this request. If this
+    // happens we may let a download through that we shouldn't have. But this is
+    // rather rare, and it is difficult to get 100% right, so we don't deal with
+    // it.
+    NavigationEntry* entry = controller->GetPendingEntry();
+    if (!entry)
+      return;
+
+    // Redirects don't count.
+    if (content::PageTransitionIsRedirect(entry->GetTransitionType()))
+      return;
+
+    if (status_ == DownloadRequestLimiter::ALLOW_ALL_DOWNLOADS ||
+        status_ == DownloadRequestLimiter::DOWNLOADS_NOT_ALLOWED) {
+      // User has either allowed all downloads or canceled all downloads. Only
+      // reset the download state if the user is navigating to a different host
+      // (or host is empty).
+      if (!initial_page_host_.empty() && !entry->GetURL().host().empty() &&
+          entry->GetURL().host() == initial_page_host_)
         return;
-
-      if (content::PageTransitionIsRedirect(entry->GetTransitionType())) {
-        // Redirects don't count.
-        return;
-      }
-
-      if (status_ == DownloadRequestLimiter::ALLOW_ALL_DOWNLOADS ||
-          status_ == DownloadRequestLimiter::DOWNLOADS_NOT_ALLOWED) {
-        // User has either allowed all downloads or canceled all downloads. Only
-        // reset the download state if the user is navigating to a different
-        // host (or host is empty).
-        if (!initial_page_host_.empty() && !entry->GetURL().host().empty() &&
-            entry->GetURL().host() == initial_page_host_) {
-          return;
-        }
-      }
-      break;
     }
-
-    case content::NOTIFICATION_WEB_CONTENTS_DESTROYED:
-      // Tab closed, no need to handle closing the dialog as it's owned by the
-      // WebContents, break so that we get deleted after switch.
-      break;
-
-    default:
-      NOTREACHED();
+  } else {
+    DCHECK_EQ(content::NOTIFICATION_WEB_CONTENTS_DESTROYED, type);
+    DCHECK_EQ(controller,
+              &content::Source<content::WebContents>(source)->GetController());
+    // Tab closed, no need to handle closing the dialog as it's owned by the
+    // WebContents.
   }
 
   NotifyCallbacks(false);
   host_->Remove(this);
 }
 
 void DownloadRequestLimiter::TabDownloadState::NotifyCallbacks(bool allow) {
   set_download_status(allow ?
       DownloadRequestLimiter::ALLOW_ALL_DOWNLOADS :
       DownloadRequestLimiter::DOWNLOADS_NOT_ALLOWED);
@@ skipping 175 matching lines @@
 
 void DownloadRequestLimiter::Remove(TabDownloadState* state) {
   DCHECK(ContainsKey(state_map_, state->web_contents()));
   state_map_.erase(state->web_contents());
   delete state;
 }
 
 // static
 DownloadRequestLimiter::TestingDelegate* DownloadRequestLimiter::delegate_ =
     NULL;