Fix three causes of blank thumbnails [2nd land]

chrome/browser/android/compositor/tab_content_manager.cc

Index: chrome/browser/android/compositor/tab_content_manager.cc
diff --git a/chrome/browser/android/compositor/tab_content_manager.cc b/chrome/browser/android/compositor/tab_content_manager.cc
index bdbdf1a306f2459fae294abbe31be80b7748de3f..67373dbc1ad7a6bc26c4dee41b669d6d45cb6ef8 100644
--- a/chrome/browser/android/compositor/tab_content_manager.cc
+++ b/chrome/browser/android/compositor/tab_content_manager.cc
@@ -217,20 +217,17 @@ void TabContentManager::CacheTab(JNIEnv* env,
   content::WebContents* web_contents = tab_android->web_contents();
   DCHECK(web_contents);
 
-  if (pending_tab_readbacks_.find(tab_id) != pending_tab_readbacks_.end())
+  if (!web_contents->GetRenderViewHost() ||
+      !web_contents->GetRenderViewHost()->GetWidget() ||
+      !web_contents->GetRenderViewHost()
+           ->GetWidget()
+           ->CanCopyFromBackingStore() ||
+      pending_tab_readbacks_.find(tab_id) != pending_tab_readbacks_.end() ||
+      pending_tab_readbacks_.size() >= kMaxReadbacks) {
     return;
+  }
 
   if (thumbnail_cache_->CheckAndUpdateThumbnailMetaData(tab_id, url)) {
-    if (!web_contents->GetRenderViewHost() ||
-        !web_contents->GetRenderViewHost()->GetWidget() ||
-        !web_contents->GetRenderViewHost()
-             ->GetWidget()
-             ->CanCopyFromBackingStore() ||
-        pending_tab_readbacks_.size() >= kMaxReadbacks) {
-      thumbnail_cache_->Remove(tab_id);
-      return;
-    }
-
     TabReadbackCallback readback_done_callback =
         base::Bind(&TabContentManager::PutThumbnailIntoCache,
                    weak_factory_.GetWeakPtr(), tab_id);