Remove CWV class and move setting User Agent to CWVWebViewConfiguration.

ios/web_view/public/cwv_web_view.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 #ifndef IOS_WEB_VIEW_PUBLIC_CWV_WEB_VIEW_H_
 #define IOS_WEB_VIEW_PUBLIC_CWV_WEB_VIEW_H_
 
 #import <ChromeWebView/cwv_export.h>
 #import <UIKit/UIKit.h>
 
 @class CWVWebViewConfiguration;
@@ skipping 36 matching lines @@
 // The current page title.
 @property(nonatomic, readonly, copy) NSString* title;
 
 // Page loading progress from 0.0 to 1.0. KVO compliant.
 //
 // It is 0.0 initially before the first navigation starts. After a navigation
 // completes, it remains at 1.0 until a new navigation starts, at which point it
 // is reset to 0.0.
 @property(nonatomic, readonly) double estimatedProgress;
 
+// Customizes the User Agent string. It should be of the format "product/1.0".
+// NOTE: It is recommended to set |product| before initializing any web views.
+//
+// Setting |product| is only guaranteed to affect web views which have not yet

[Eugene But (OOO till 7-30), 2017/04/11 17:52:42]

Do you want to document how calling this API will actually affect final UA
string?

[michaeldo, 2017/04/11 21:57:03]

I added a note that |product| is inserted into the UA string. I don't know if
it's helpful to show a full example here as it will change and the documentation
will likely be out of date. WDYT?

[Eugene But (OOO till 7-30), 2017/04/12 00:46:17]

I think it is helpful to explain why clients would want to call this method and
what will happen if they don't call it (I assume that UA will look silly in this
case).

[Eugene But (OOO till 7-30), 2017/04/12 17:48:27]

Please take a look at this comment.

[michaeldo, 2017/04/12 18:22:55]

I've added example UA.

+// been initialized. However, exisiting web views could also be affected
+// depending upon their internal state.
++ (void)setUserAgentProduct:(NSString*)product;
+
 // |configuration| must not be null
 - (instancetype)initWithFrame:(CGRect)frame
                 configuration:(CWVWebViewConfiguration*)configuration
     NS_DESIGNATED_INITIALIZER;
 
 - (instancetype)initWithFrame:(CGRect)frame NS_UNAVAILABLE;
 - (instancetype)initWithCoder:(NSCoder*)aDecoder NS_UNAVAILABLE;
 
 // Navigates backwards or forwards by one page.  Does nothing if the
 // corresponding |canGoBack| or |canGoForward| method returns NO.
@@ skipping 11 matching lines @@
 - (void)loadRequest:(NSURLRequest*)request;
 
 // Evaluates a JavaScript string.
 // The completion handler is invoked when script evaluation completes.
 - (void)evaluateJavaScript:(NSString*)javaScriptString
          completionHandler:(void (^)(id, NSError*))completionHandler;
 
 @end
 
 #endif  // IOS_WEB_VIEW_PUBLIC_CWV_WEB_VIEW_H_