Do not navigate on loading iframes in StaticHTMLViewController.

ios/chrome/browser/ui/static_content/static_html_view_controller.mm

Index: ios/chrome/browser/ui/static_content/static_html_view_controller.mm
diff --git a/ios/chrome/browser/ui/static_content/static_html_view_controller.mm b/ios/chrome/browser/ui/static_content/static_html_view_controller.mm
index e22d51be30dfc15ce6ccfdcb8eba00aa3f3cc1c9..4d869068338753aebada5dcf650774ca6ef3810c 100644
--- a/ios/chrome/browser/ui/static_content/static_html_view_controller.mm
+++ b/ios/chrome/browser/ui/static_content/static_html_view_controller.mm
@@ -84,8 +84,10 @@
 - (NSURL*)resourceURL;
 // Ensures that webView_ has been created, creating it if necessary.
 - (void)ensureWebViewCreated;
-// Determines if the page load should begin based on the current |resourceURL|.
-- (BOOL)shouldStartLoadWithRequest:(NSURLRequest*)request;
+// Determines if the page load should begin based on the current |resourceURL|
+// and the navigation type |type|.
+- (BOOL)shouldStartLoadWithRequest:(NSURLRequest*)request
+                              type:(WKNavigationType)type;

[Eugene But (OOO till 7-30), 2016/12/22 16:21:56]

nit: s/type/navigationType:

[Olivier, 2016/12/22 16:42:59]

Done.

[Eugene But (OOO till 7-30), 2016/12/22 17:37:51]

Sorry I meant words before arguments (s/type:/navigationType:) but I guess you
won't need this anymore :)

 @end
 
 @implementation StaticHtmlViewController
@@ -199,9 +201,11 @@
     decidePolicyForNavigationAction:(WKNavigationAction*)navigationAction
                     decisionHandler:
                         (void (^)(WKNavigationActionPolicy))decisionHandler {
-  decisionHandler([self shouldStartLoadWithRequest:navigationAction.request]
-                      ? WKNavigationActionPolicyAllow
-                      : WKNavigationActionPolicyCancel);
+  decisionHandler(
+      [self shouldStartLoadWithRequest:navigationAction.request
+                                  type:navigationAction.navigationType]
+          ? WKNavigationActionPolicyAllow
+          : WKNavigationActionPolicyCancel);
 }
 
 #pragma mark -
@@ -222,13 +226,16 @@
 #pragma mark -
 #pragma mark Private
 
-- (BOOL)shouldStartLoadWithRequest:(NSURLRequest*)request {
+- (BOOL)shouldStartLoadWithRequest:(NSURLRequest*)request
+                              type:(WKNavigationType)type {
   // Only allow displaying the URL which correspond to the authorized resource.
   if ([[request URL] isEqual:[self resourceURL]])
     return YES;
 
-  // All other URLs will be loaded by our UrlLoader if we have one.
-  if (loader_) {
+  // All other navigation URLs will be loaded by our UrlLoader if we have one.

[Eugene But (OOO till 7-30), 2016/12/22 16:21:56]

nit: Please avoid "we" in the comments (go/avoidwe)

[Olivier, 2016/12/22 16:42:59]

I did not add the we :)
Removed.

+  // If type is |WKNavigationTypeOther|, the URL corresponds to an external

[Eugene But (OOO till 7-30), 2016/12/22 16:21:56]

What does "external resource mean"? I think WKNavigationTypeOther can represent
regular link clicks:
https://cs.chromium.org/chromium/src/ios/web/web_state/ui/crw_web_controller....

[Olivier, 2016/12/22 16:42:59]

Clicking on regular link is WKNavigationTypeLinkActivated
https://developer.apple.com/reference/webkit/wknavigationtype/wknavigationtyp...

I can add another check like 
[_webView isLoading]

I checked and the element causing the navigation is an iframe. Updated the
comment.

+  // resource and should not be loaded at all.
+  if (loader_ && type != WKNavigationTypeOther) {
     dispatch_async(dispatch_get_main_queue(), ^{
       [loader_ loadURL:net::GURLWithNSURL([request URL])
                    referrer:referrer_