Remove about:srcdoc url conversion.

content/browser/child_process_security_policy_impl.cc

Index: content/browser/child_process_security_policy_impl.cc
diff --git a/content/browser/child_process_security_policy_impl.cc b/content/browser/child_process_security_policy_impl.cc
index f1aa1c74d71df72530020a7be37b54ab32fee7f7..a0ee91ac9440d5ff174fe2c1f69f04768faf8304 100644
--- a/content/browser/child_process_security_policy_impl.cc
+++ b/content/browser/child_process_security_policy_impl.cc
@@ -626,8 +626,8 @@ bool ChildProcessSecurityPolicyImpl::CanRequestURL(
     return false;  // Can't request invalid URLs.
 
   if (IsPseudoScheme(url.scheme())) {
-    // Every child process can request <about:blank>.
-    if (base::LowerCaseEqualsASCII(url.spec(), url::kAboutBlankURL))
+    // Every child process can request <about:blank> and <about:srcdoc>
+    if (url == url::kAboutBlankURL || url == content::kAboutSrcDocURL)
       return true;
     // URLs like <about:version>, <about:crash>, <view-source:...> shouldn't be
     // requestable by any child process.  Also, this case covers
@@ -666,7 +666,7 @@ bool ChildProcessSecurityPolicyImpl::CanCommitURL(int child_id,
 
   // Of all the pseudo schemes, only about:blank is allowed to commit.
   if (IsPseudoScheme(url.scheme()))
-    return base::LowerCaseEqualsASCII(url.spec(), url::kAboutBlankURL);
+    return url == url::kAboutBlankURL;
 
   // Blob and filesystem URLs require special treatment; validate the inner
   // origin they embed.