Reland of [ios] Implemented LoadHtml w/o using data:// URLs.

ios/web/web_state/ui/crw_web_controller.mm

 // Copyright 2012 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.
 
 #import "ios/web/web_state/ui/crw_web_controller.h"
 
 #import <WebKit/WebKit.h>
 
 #import <objc/runtime.h>
 #include <stddef.h>
@@ skipping 4749 matching lines @@
                         [self handleLoadError:loadError inMainFrame:YES];
                       else
                         self.webStateImpl->SetContentsMimeType("text/html");
                     }];
 }
 
 - (void)loadHTML:(NSString*)HTML forURL:(const GURL&)URL {
   // Remove the transient content view.
   [self clearTransientContentView];
 
-  DLOG_IF(WARNING, !_webView) << "_webView null while trying to load HTML";
   _loadPhase = web::LOAD_REQUESTED;
+  [self ensureWebViewCreated];
+  DCHECK(_webView) << "_webView null while trying to load HTML";
   [_webView loadHTMLString:HTML baseURL:net::NSURLWithGURL(URL)];
 }
 
 - (void)loadHTML:(NSString*)HTML forAppSpecificURL:(const GURL&)URL {
   CHECK(web::GetWebClient()->IsAppSpecificURL(URL));
   [self loadHTML:HTML forURL:URL];
 }
 
 - (void)loadHTMLForCurrentURL:(NSString*)HTML {
   [self loadHTML:HTML forURL:self.currentURL];
@@ skipping 186 matching lines @@
 
   BOOL allowLoad = [self shouldAllowLoadWithNavigationAction:action];
 
   if (allowLoad) {
     allowLoad = self.webStateImpl->ShouldAllowRequest(action.request);
     if (!allowLoad && action.targetFrame.mainFrame) {
       [_pendingNavigationInfo setCancelled:YES];
     }
   }
 
-  if (!allowLoad && action.targetFrame.isMainFrame) {
-    // WKWebView will stop this navigation without calling any further
-    // callbacks, so change load phase to loaded now.
-    _loadPhase = web::PAGE_LOADED;
-    _webStateImpl->SetIsLoading(false);
-  }
-
   decisionHandler(allowLoad ? WKNavigationActionPolicyAllow
                             : WKNavigationActionPolicyCancel);
 }
 
 - (void)webView:(WKWebView*)webView
     decidePolicyForNavigationResponse:(WKNavigationResponse*)navigationResponse
                       decisionHandler:
                           (void (^)(WKNavigationResponsePolicy))handler {
   if ([navigationResponse.response isKindOfClass:[NSHTTPURLResponse class]]) {
     // Create HTTP headers from the response.
@@ skipping 640 matching lines @@
   }
 
   return web::WEB_VIEW_DOCUMENT_TYPE_GENERIC;
 }
 
 - (NSString*)refererFromNavigationAction:(WKNavigationAction*)action {
   return [action.request valueForHTTPHeaderField:@"Referer"];
 }
 
 @end