don't load first message in collapsed thread before displaying summary, r=asuth, sr=standard8, 495304

mail/base/content/SearchDialog.js

@@ -527,7 +527,7 @@ nsMsgSearchCommandUpdater.prototype =
     SetNextMessageAfterDelete();
   },
 
-  summarizeSelection : function() {},
+  summarizeSelection : function() {return false},
 
   QueryInterface : function(iid)
   {

mail/base/content/messageWindow.js

@@ -188,7 +188,7 @@ nsMsgDBViewCommandUpdater.prototype =
     SetNextMessageAfterDelete();
   },
 
-  summarizeSelection : function() {},
+  summarizeSelection : function() {return false},
 
   QueryInterface : function(iid)
   {

mail/base/content/threadPane.js

@@ -121,12 +121,12 @@ nsMsgDBViewCommandUpdater.prototype =
     let selectedMsgUris = GetSelectedMessages();
     if (!selectedMsgUris || (selectedMsgUris.length == 1)) {
       pickMessagePane("singlemessage");
-      return;
+      return false;
     }
 
     if (! gPrefBranch.getBoolPref("mail.operate_on_msgs_in_collapsed_threads")) {
       ClearMessagePane();
-      return;
+      return false;
     }
 
     let firstThreadId = messenger.msgHdrFromURI(selectedMsgUris[0]).threadId;
@@ -138,6 +138,7 @@ nsMsgDBViewCommandUpdater.prototype =
     }
     // must be just one thread.
     summarizeThread(selectedMsgUris);
+    return true;
   },
 
   QueryInterface : function(iid)

mailnews/base/public/nsIMsgDBView.idl

@@ -442,7 +442,9 @@ interface nsIMsgDBViewCommandUpdater : nsISupports
   
   /**
   * tell the front end that the selection has changed, and may need to be
-  * resummarized
+  * resummarized.
+  * 
+  * @return   true if we did summarize, false otherwise.
   */
-  void summarizeSelection();
+  boolean summarizeSelection();
 };

mailnews/base/src/nsMsgDBView.cpp

@@ -1045,8 +1045,14 @@ NS_IMETHODIMP nsMsgDBView::SelectionChanged()
     if (!NonDummyMsgSelected(indices, numSelected))
       commandsNeedDisablingBecauseOfSelection = PR_TRUE;
   }
+  PRBool selectionSummarized = PR_FALSE;
+  // let the front-end adjust the message pane appropriately with either
+  // the message body, or a summary of the selection
+  if (mCommandUpdater)
+    mCommandUpdater->SummarizeSelection(&selectionSummarized);
+
   // if only one item is selected then we want to display a message
-  if (numSelected == 1)
+  if (numSelected == 1 && !selectionSummarized)
   {
     PRInt32 startRange;
     PRInt32 endRange;
@@ -1073,11 +1079,6 @@ NS_IMETHODIMP nsMsgDBView::SelectionChanged()
     m_currentlyDisplayedViewIndex = nsMsgViewIndex_None;
   }
 
-  // let the front-end adjust the message pane appropriately with either
-  // the message body, or a summary of the selection
-  if (mCommandUpdater)
-    mCommandUpdater->SummarizeSelection();
-
   // determine if we need to push command update notifications out to the UI or not.
 
   // we need to push a command update notification iff, one of the following conditions are met

suite/mailnews/messageWindow.js

@@ -184,7 +184,7 @@ nsMsgDBViewCommandUpdater.prototype =
     SetNextMessageAfterDelete();
   },
 
-  summarizeSelection: function() {},
+  summarizeSelection: function() {return false},
 
   QueryInterface : function(iid)
   {

suite/mailnews/search/SearchDialog.js

@@ -527,7 +527,7 @@ nsMsgSearchCommandUpdater.prototype =
     SetNextMessageAfterDelete();
   },
 
-  summarizeSelection: function() {},
+  summarizeSelection: function() {return false},
 
   QueryInterface : function(iid)
   {

suite/mailnews/threadPane.js

@@ -116,7 +116,7 @@ nsMsgDBViewCommandUpdater.prototype =
     SetNextMessageAfterDelete();
   },
 
-  summarizeSelection: function() {},
+  summarizeSelection: function() {return false},
 
   QueryInterface : function(iid)
    {