Bug 1431924 - Do not use URLParams::ParseInput in PageThumbsProtocol::ParseProtocolURL; r=bz

MozReview-Commit-ID: 79Pg9Vlq8Bu

--HG--
extra : rebase_source : 268407fe4f206751c66c66bd378ea8ff112b816d

dom/url/URLSearchParams.cpp

@@ -216,6 +216,47 @@ URLParams::Parse(const nsACString& aInput, ForEachIterator& aIterator)
   return true;
 }
 
+class MOZ_STACK_CLASS ExtractURLParam final
+  : public URLParams::ForEachIterator
+{
+public:
+  explicit ExtractURLParam(const nsAString& aName, nsAString& aValue)
+    : mName(aName), mValue(aValue)
+  {}
+
+  bool URLParamsIterator(const nsAString& aName,
+                         const nsAString& aValue) override
+  {
+    if (mName == aName) {
+      mValue = aValue;
+      return false;
+    }
+    return true;
+  }
+
+private:
+  const nsAString& mName;
+  nsAString& mValue;
+};
+
+
+/**
+ * Extracts the first form-urlencoded parameter named `aName` from `aInput`.
+ * @param aRange The input to parse.
+ * @param aName The name of the parameter to extract.
+ * @param aValue The value of the extracted parameter, void if not found.
+ * @return Whether the parameter was found in the form-urlencoded.
+ */
+/* static */ bool
+URLParams::Extract(const nsACString& aInput,
+                   const nsAString& aName,
+                   nsAString& aValue)
+{
+  aValue.SetIsVoid(true);
+  ExtractURLParam iterator(aName, aValue);
+  return !URLParams::Parse(aInput, iterator);
+}
+
 class MOZ_STACK_CLASS PopulateIterator final
   : public URLParams::ForEachIterator
 {

dom/url/URLSearchParams.h

@@ -53,6 +53,9 @@ public:
   static bool
   Parse(const nsACString& aInput, ForEachIterator& aIterator);
 
+  static bool
+  Extract(const nsACString& aInput, const nsAString& aName, nsAString& aValue);
+
   void
   ParseInput(const nsACString& aInput);
 

toolkit/components/thumbnails/PageThumbsProtocol.cpp

@@ -138,10 +138,9 @@ PageThumbsProtocol::ParseProtocolURL(nsIURI* aURI, nsString& aParsedURL)
     return NS_ERROR_MALFORMED_URI;
   }
 
-  URLParams params;
-  params.ParseInput(Substring(path, queryBegins + 1));
-
-  params.Get(NS_LITERAL_STRING("url"), aParsedURL);
+  URLParams::Extract(Substring(path, queryBegins + 1),
+                     NS_LITERAL_STRING("url"),
+                     aParsedURL);
 
   // If there's no URL as part of the query params, there will be no thumbnail
   if (aParsedURL.IsVoid()) {