Bug 611503 Constructing an nsTDependentString from an nsTAString makes no sense r=dbaron,dwitte

dom/base/nsDOMClassInfo.cpp

@@ -8120,7 +8120,7 @@ nsDOMStringMapSH::Enumerate(nsIXPConnectWrappedNative *wrapper, JSContext *cx,
   NS_ENSURE_SUCCESS(rv, rv);
 
   for (PRUint32 i = 0; i < properties.Length(); ++i) {
-    nsDependentString prop(properties[i]);
+    nsString& prop(properties[i]);
     *_retval = JS_DefineUCProperty(cx, obj, prop.get(), prop.Length(),
                                    JSVAL_VOID, nsnull, nsnull,
                                    JSPROP_ENUMERATE | JSPROP_SHARED);

layout/style/nsCSSValue.cpp

@@ -922,8 +922,7 @@ nsCSSValue::AppendToString(nsCSSProperty aProperty, nsAString& aResult) const
     aResult.Append(NS_LITERAL_STRING("-moz-element(#"));
     nsAutoString tmpStr;
     GetStringValue(tmpStr);
-    nsStyleUtil::AppendEscapedCSSIdent(
-      nsDependentString(tmpStr), aResult);
+    nsStyleUtil::AppendEscapedCSSIdent(tmpStr, aResult);
     aResult.Append(NS_LITERAL_STRING(")"));
   }
   else if (eCSSUnit_Percent == unit) {

netwerk/cookie/CookieServiceParent.cpp

@@ -95,8 +95,9 @@ CookieServiceParent::RecvSetCookieString(const IPC::URI& aHost,
   if (!hostURI)
     return false;
 
+  nsDependentCString cookieString(aCookieString, 0);
   mCookieService->SetCookieStringInternal(hostURI, aIsForeign,
-                                          aCookieString, aServerTime,
+                                          cookieString, aServerTime,
                                           aFromHttp);
   return true;
 }

netwerk/cookie/nsCookieService.cpp

@@ -1495,7 +1495,7 @@ nsCookieService::SetCookieStringCommon(nsIURI *aHostURI,
 void
 nsCookieService::SetCookieStringInternal(nsIURI             *aHostURI,
                                          bool                aIsForeign,
-                                         const nsCString &aCookieHeader,
+                                         nsDependentCString &aCookieHeader,
                                          const nsCString    &aServerTime,
                                          PRBool              aFromHttp)
 {
@@ -1550,9 +1550,8 @@ nsCookieService::SetCookieStringInternal(nsIURI          *aHostURI,
   }
 
   // process each cookie in the header
-  nsDependentCString cookieHeader(aCookieHeader);
-  while (SetCookieInternal(aHostURI, baseDomain, requireHostMatch,
-                           cookieStatus, cookieHeader, serverTime, aFromHttp)) {
+  while (SetCookieInternal(aHostURI, baseDomain, requireHostMatch, cookieStatus,
+                           aCookieHeader, serverTime, aFromHttp)) {
     // document.cookie can only set one cookie at a time
     if (!aFromHttp)
       break;

netwerk/cookie/nsCookieService.h

@@ -263,7 +263,7 @@ class nsCookieService : public nsICookieService
     nsresult                      GetCookieStringCommon(nsIURI *aHostURI, nsIChannel *aChannel, bool aHttpBound, char** aCookie);
     void                          GetCookieStringInternal(nsIURI *aHostURI, bool aIsForeign, PRBool aHttpBound, nsCString &aCookie);
     nsresult                      SetCookieStringCommon(nsIURI *aHostURI, const char *aCookieHeader, const char *aServerTime, nsIChannel *aChannel, bool aFromHttp);
-    void                          SetCookieStringInternal(nsIURI *aHostURI, bool aIsForeign, const nsCString &aCookieHeader, const nsCString &aServerTime, PRBool aFromHttp);
+    void                          SetCookieStringInternal(nsIURI *aHostURI, bool aIsForeign, nsDependentCString &aCookieHeader, const nsCString &aServerTime, PRBool aFromHttp);
     PRBool                        SetCookieInternal(nsIURI *aHostURI, const nsCString& aBaseDomain, PRBool aRequireHostMatch, CookieStatus aStatus, nsDependentCString &aCookieHeader, PRInt64 aServerTime, PRBool aFromHttp);
     void                          AddInternal(const nsCString& aBaseDomain, nsCookie *aCookie, PRInt64 aCurrentTimeInUsec, nsIURI *aHostURI, const char *aCookieHeader, PRBool aFromHttp);
     void                          RemoveCookieFromList(const nsListIter &aIter, mozIStorageBindingParamsArray *aParamsArray = NULL);

widget/src/xpwidgets/nsXPLookAndFeel.cpp

@@ -330,9 +330,7 @@ nsXPLookAndFeel::ColorPrefChanged (unsigned int index, const char *prefName)
   if (!colorStr.IsEmpty()) {
     nscolor thecolor;
     if (colorStr[0] == PRUnichar('#')) {
-      if (NS_HexToRGB(nsDependentString(
-                        Substring(colorStr, 1, colorStr.Length() - 1)),
-                      &thecolor)) {
+      if (NS_HexToRGB(nsDependentString(colorStr, 1), &thecolor)) {
         PRInt32 id = NS_PTR_TO_INT32(index);
         CACHE_COLOR(id, thecolor);
       }

xpcom/string/public/nsTDependentString.h

@@ -91,11 +91,10 @@ class nsTDependentString_CharT : public nsTString_CharT
           AssertValid();
         }
 
-      explicit
-      nsTDependentString_CharT( const substring_type& str )
-        : string_type(const_cast<char_type*>(str.Data()), str.Length(), F_TERMINATED)
+      nsTDependentString_CharT( const string_type& str, PRUint32 startPos )
+        : string_type()
         {
-          AssertValid();
+          Rebind(str, startPos);
         }
 
       // Create a nsTDependentSubstring to be bound later
@@ -124,6 +123,8 @@ class nsTDependentString_CharT : public nsTString_CharT
           Rebind(start, PRUint32(end - start));
         }
 
+      void Rebind( const string_type&, PRUint32 startPos );
+
     private:
       
       // NOT USED

xpcom/string/src/nsTDependentString.cpp

@@ -48,3 +48,20 @@ nsTDependentString_CharT::Rebind( const char_type* data, size_type length )
     SetDataFlags(F_TERMINATED);
     AssertValid();
   }
+
+void
+nsTDependentString_CharT::Rebind( const string_type& str, PRUint32 startPos )
+  {
+    // If we currently own a buffer, release it.
+    Finalize();
+
+    size_type strLength = str.Length();
+
+    if (startPos > strLength)
+      startPos = strLength;
+
+    mData = const_cast<char_type*>(str.Data()) + startPos;
+    mLength = strLength - startPos;
+
+    SetDataFlags(F_TERMINATED);
+  }