Update Polymer from 1.2.1 -> 1.2.3

third_party/polymer/v1_0/components-chromium/iron-fit-behavior/README.md

Index: third_party/polymer/v1_0/components-chromium/iron-fit-behavior/README.md
diff --git a/third_party/polymer/v1_0/components-chromium/iron-fit-behavior/README.md b/third_party/polymer/v1_0/components-chromium/iron-fit-behavior/README.md
index 8f4fc7631166d25bfbd15252e15ce34142c9ecac..d8ac001a9a36cfc38635387cb5649409251c3fed 100644
--- a/third_party/polymer/v1_0/components-chromium/iron-fit-behavior/README.md
+++ b/third_party/polymer/v1_0/components-chromium/iron-fit-behavior/README.md
@@ -1,3 +1,34 @@
-# iron-fit-behavior
 
-Fits an element in the window, or another element.
+<!---
+
+This README is automatically generated from the comments in these files:
+iron-fit-behavior.html
+
+Edit those files, and our readme bot will duplicate them over here!
+Edit this file, and the bot will squash your changes :)
+
+-->
+
+[![Build Status](https://travis-ci.org/PolymerElements/iron-fit-behavior.svg?branch=master)](https://travis-ci.org/PolymerElements/iron-fit-behavior)
+
+_[Demo and API Docs](https://elements.polymer-project.org/elements/iron-fit-behavior)_
+
+
+##Polymer.IronFitBehavior
+
+
+Polymer.IronFitBehavior fits an element in another element using `max-height` and `max-width`, and
+optionally centers it in the window or another element.
+
+The element will only be sized and/or positioned if it has not already been sized and/or positioned
+by CSS.
+
+CSS properties               | Action
+-----------------------------|-------------------------------------------
+`position` set               | Element is not centered horizontally or vertically
+`top` or `bottom` set        | Element is not vertically centered
+`left` or `right` set        | Element is not horizontally centered
+`max-height` or `height` set | Element respects `max-height` or `height`
+`max-width` or `width` set   | Element respects `max-width` or `width`
+
+