Implement CSP check for manifest fetching

Source/core/frame/csp/ContentSecurityPolicy.cpp

Index: Source/core/frame/csp/ContentSecurityPolicy.cpp
diff --git a/Source/core/frame/csp/ContentSecurityPolicy.cpp b/Source/core/frame/csp/ContentSecurityPolicy.cpp
index 80af84f042786d4b885d3329b8afde7e1ac9fc02..798b757f6641dd0df5979629cd7383c11e0173d9 100644
--- a/Source/core/frame/csp/ContentSecurityPolicy.cpp
+++ b/Source/core/frame/csp/ContentSecurityPolicy.cpp
@@ -89,6 +89,10 @@ const char ContentSecurityPolicy::PluginTypes[] = "plugin-types";
 const char ContentSecurityPolicy::ReflectedXSS[] = "reflected-xss";
 const char ContentSecurityPolicy::Referrer[] = "referrer";
 
+// Manifest Directives
+// https://w3c.github.io/manifest/#content-security-policy
+const char ContentSecurityPolicy::ManifestSrc[] = "manifest-src";
+
 bool ContentSecurityPolicy::isDirectiveName(const String& name)
 {
     return (equalIgnoringCase(name, ConnectSrc)
@@ -109,6 +113,7 @@ bool ContentSecurityPolicy::isDirectiveName(const String& name)
         || equalIgnoringCase(name, PluginTypes)
         || equalIgnoringCase(name, ReflectedXSS)
         || equalIgnoringCase(name, Referrer)
+        || equalIgnoringCase(name, ManifestSrc)
     );
 }
 
@@ -533,6 +538,11 @@ bool ContentSecurityPolicy::allowWorkerContextFromSource(const KURL& url, Conten
         isAllowedByAllWithURL<&CSPDirectiveList::allowScriptFromSource>(m_policies, url, reportingStatus);
 }
 
+bool ContentSecurityPolicy::allowManifestFromSource(const KURL& url, ContentSecurityPolicy::ReportingStatus reportingStatus) const
+{
+    return isAllowedByAllWithURL<&CSPDirectiveList::allowManifestFromSource>(m_policies, url, reportingStatus);
+}
+
 bool ContentSecurityPolicy::isActive() const
 {
     return !m_policies.isEmpty();