[tracing] Move math utilities from base into their own subdirectory (attempt 2)

tracing/tracing/extras/chrome/layout_object.html

Index: tracing/tracing/extras/chrome/layout_object.html
diff --git a/tracing/tracing/extras/chrome/layout_object.html b/tracing/tracing/extras/chrome/layout_object.html
index f23a181ab0630c3066049b1fe6f606c087af808f..e9528ab243288c9d8340d77263cff806860f8cd8 100644
--- a/tracing/tracing/extras/chrome/layout_object.html
+++ b/tracing/tracing/extras/chrome/layout_object.html
@@ -46,9 +46,9 @@ tr.exportTo('tr.e.chrome', function() {
     this.childLayoutObjects_ = [];
     this.otherProperties_ = {};
     this.tag_ = args.tag;
-    this.relativeRect_ = tr.b.Rect.fromXYWH(
+    this.relativeRect_ = tr.b.math.Rect.fromXYWH(
         args.relX, args.relY, args.width, args.height);
-    this.absoluteRect_ = tr.b.Rect.fromXYWH(
+    this.absoluteRect_ = tr.b.math.Rect.fromXYWH(
         args.absX, args.absY, args.width, args.height);
     this.isFloat_ = args.float;
     this.isStickyPositioned_ = args.stickyPositioned;