-fix VirtualFolders in Eclipse under Windows

Under Windows "locationURI" must be used for virtual folders, while
"location" must be used only for linked folders. Under Linux it doesn't
seem to matter.

Alex

Source/cmExtraEclipseCDT4Generator.cxx

@@ -403,7 +403,7 @@ void cmExtraEclipseCDT4Generator::CreateProjectFile()
   // for each sub project create a linked resource to the source dir
   // - only if it is an out-of-source build
   this->AppendLinkedResource(fout, "[Subprojects]",
-                             "virtual:/virtual");
+                             "virtual:/virtual", true);
 
   for (std::map<cmStdString, std::vector<cmLocalGenerator*> >::const_iterator
        it = this->GlobalGenerator->GetProjectMap().begin();
@@ -1082,17 +1082,24 @@ void cmExtraEclipseCDT4Generator
 void cmExtraEclipseCDT4Generator
 ::AppendLinkedResource (cmGeneratedFileStream& fout,
                         const std::string&     name,
-                        const std::string&     path)
+                        const std::string&     path,
+                        bool isVirtualFolder)
 {
+  const char* locationTag = "location";
+  if (isVirtualFolder) // ... and not a linked folder
+    {
+    locationTag = "locationURI";
+    }
+
   fout <<
     "\t\t<link>\n"
     "\t\t\t<name>"
     << cmExtraEclipseCDT4Generator::EscapeForXML(name)
     << "</name>\n"
     "\t\t\t<type>2</type>\n"
-    "\t\t\t<locationURI>"
+    "\t\t\t<" << locationTag << ">"
     << cmExtraEclipseCDT4Generator::EscapeForXML(path)
-    << "</locationURI>\n"
+    << "</" << locationTag << ">\n"
     "\t\t</link>\n"
     ;
 }

Source/cmExtraEclipseCDT4Generator.h

@@ -87,7 +87,8 @@ private:
 
   static void AppendLinkedResource (cmGeneratedFileStream& fout,
                                     const std::string&     name,
-                                    const std::string&     path);
+                                    const std::string&     path,
+                                    bool isVirtualFolder = false);
 
   bool AppendOutLinkedResource(cmGeneratedFileStream& fout,
                                const std::string&     defname,