Fix process handle leak (#136)

Author: dremin

src/ManagedShell.Common/Helpers/ShellHelper.cs

@@ -340,6 +340,7 @@ public static string GetPathForWindowHandle(IntPtr hWnd)
                 // get path
                 int len = outFileName.Capacity;
                 QueryFullProcessImageName(hProc, 0, outFileName, ref len);
+                CloseHandle(hProc);
             }
 
             return outFileName.ToString();
@@ -403,7 +404,7 @@ public static string GetAppUserModelIdForHandle(IntPtr hWnd)
                 StringBuilder outAumid = new StringBuilder((int)len);
 
                 GetApplicationUserModelId(hProcess, ref len, outAumid);
-                CloseHandle((int)hProcess);
+                CloseHandle(hProcess);
 
                 if (outAumid.Length > 0)
                 {

src/ManagedShell.Interop/NativeMethods.Kernel32.cs

@@ -71,6 +71,9 @@ public static extern SafeFileHandle CreateFile([MarshalAs(UnmanagedType.LPTStr)]
         [DllImport(Kernel32_DllName)]
         public static extern Int32 CloseHandle(Int32 Handle);
 
+        [DllImport(Kernel32_DllName)]
+        public static extern bool CloseHandle(IntPtr Handle);
+
         [DllImport(Kernel32_DllName, SetLastError = true, CallingConvention = CallingConvention.Winapi)]
         [return: MarshalAs(UnmanagedType.Bool)]
         public static extern bool IsWow64Process(

src/ManagedShell.WindowsTray/ExplorerTrayService.cs

@@ -106,7 +106,7 @@ private void GetTrayItems()
 
             VirtualFreeEx(hProcess, hBuffer, 0, AllocationType.Release);
 
-            CloseHandle((int)hProcess);
+            CloseHandle(hProcess);
         }
 
         private IntPtr FindExplorerTrayToolbarHwnd()