DevTools: fix console to tail messages on devtools with zoomfactor != 1

Source/devtools/front_end/DOMExtension.js

Index: Source/devtools/front_end/DOMExtension.js
diff --git a/Source/devtools/front_end/DOMExtension.js b/Source/devtools/front_end/DOMExtension.js
index 5fd139bfa2dd6cce6a2709d4657200278855370d..e1401f9fb9185d8e4c7e3b6f7b038f739d3ee896 100644
--- a/Source/devtools/front_end/DOMExtension.js
+++ b/Source/devtools/front_end/DOMExtension.js
@@ -175,8 +175,10 @@ Element.prototype.positionAt = function(x, y, relativeTo)
 
 Element.prototype.isScrolledToBottom = function()
 {
-    // This code works only for 0-width border
-    return this.scrollTop + this.clientHeight === this.scrollHeight;
+    // This code works only for 0-width border.
+    // Both clientHeight and scrollHeight are rounded to integer values, so we tolerate
+    // one pixel error.
+    return Math.abs(this.scrollTop + this.clientHeight - this.scrollHeight) <= 1;
 }
 
 /**