DevTools: clicking in console messages should not jump to bottom

third_party/WebKit/Source/devtools/front_end/console/ConsoleView.js

Index: third_party/WebKit/Source/devtools/front_end/console/ConsoleView.js
diff --git a/third_party/WebKit/Source/devtools/front_end/console/ConsoleView.js b/third_party/WebKit/Source/devtools/front_end/console/ConsoleView.js
index be61b1a8bbe8206cb165e078dad479ca8235a504..a95d73deba9aafe78e7da3068766c0aab46cecce 100644
--- a/third_party/WebKit/Source/devtools/front_end/console/ConsoleView.js
+++ b/third_party/WebKit/Source/devtools/front_end/console/ConsoleView.js
@@ -115,6 +115,7 @@ Console.ConsoleView = class extends UI.VBox {
     this._viewport.contentElement().classList.add('console-group', 'console-group-messages');
     this._contentsElement.appendChild(this._viewport.element);
     this._messagesElement = this._viewport.element;
+    this._messagesElement.tabIndex = -1;

[luoe, 2017/04/24 22:28:33]

Currently on ToT, using up/down/pageup/pagedown keys in the console viewport no
longer scrolls.  By doing this, the viewport is focusable, restoring the old
behavior.  I haven't done a bisect yet to find out when it broke.

     this._messagesElement.id = 'console-messages';
     this._messagesElement.classList.add('monospace');
     this._messagesElement.addEventListener('click', this._messagesClicked.bind(this), true);
@@ -309,8 +310,6 @@ Console.ConsoleView = class extends UI.VBox {
   focus() {
     if (this._prompt.hasFocus())
       return;
-    // Set caret position before setting focus in order to avoid scrolling
-    // by focus().

[luoe, 2017/04/24 22:28:33]

This is no longer the case.  Calling moveCaretToEndOfPrompt() will always try to
scroll.

     this._prompt.moveCaretToEndOfPrompt();
     this._prompt.focus();
   }
@@ -666,8 +665,11 @@ Console.ConsoleView = class extends UI.VBox {
    */
   _messagesClicked(event) {
     var targetElement = event.deepElementFromPoint();
-    if (!targetElement || targetElement.isComponentSelectionCollapsed())
+    if (!targetElement || this._viewport.element.isScrolledToBottom())
       this.focus();

[luoe, 2017/04/24 22:28:33]

I think we still need to keep 2 paths.  When you click on the whitespace
underneath the prompt, it should still move the prompt cursor to the end, which
is the behavior on stable.

+    else if (targetElement.isComponentSelectionCollapsed())
+      this._prompt.focus();
+
     var groupMessage = event.target.enclosingNodeOrSelfWithClass('console-group-title');
     if (!groupMessage)
       return;