VideoCaptureDeviceWin: correct some typos and docs.

media/video/capture/win/video_capture_device_win.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "media/video/capture/win/video_capture_device_win.h"
 
 #include <ks.h>
 #include <ksmedia.h>
 
 #include <algorithm>
@@ skipping 35 matching lines @@
   ScopedComPtr<IBaseFilter> capture_filter;
   DWORD fetched = 0;
   while (enum_moniker->Next(1, moniker.Receive(), &fetched) == S_OK) {
     ScopedComPtr<IPropertyBag> prop_bag;
     hr = moniker->BindToStorage(0, 0, IID_IPropertyBag, prop_bag.ReceiveVoid());
     if (FAILED(hr)) {
       moniker.Release();
       continue;
     }
 
-    // Find the description or friendly name.
+    // Find the device via DevicePath, Description or FriendlyName, whichever is
+    // available first.
     static const wchar_t* kPropertyNames[] = {
       L"DevicePath", L"Description", L"FriendlyName"
     };
     ScopedVariant name;
     for (size_t i = 0;
          i < arraysize(kPropertyNames) && name.type() != VT_BSTR; ++i) {
       prop_bag->Read(kPropertyNames[i], name.Receive(), 0);
     }
     if (name.type() == VT_BSTR) {
       std::string device_path(base::SysWideToUTF8(V_BSTR(&name)));
@@ skipping 27 matching lines @@
     DWORD return_value;
     hr = ks_property->Get(AMPROPSETID_Pin, AMPROPERTY_PIN_CATEGORY, NULL, 0,
                           &pin_category, sizeof(pin_category), &return_value);
     if (SUCCEEDED(hr) && (return_value == sizeof(pin_category))) {
       found = (pin_category == category);
     }
   }
   return found;
 }
 
-// Finds a IPin on a IBaseFilter given the direction an category.
+// Finds an IPin on an IBaseFilter given the direction and category.
 // static
 ScopedComPtr<IPin> VideoCaptureDeviceWin::GetPin(IBaseFilter* filter,
                                                  PIN_DIRECTION pin_dir,
                                                  REFGUID category) {
   ScopedComPtr<IPin> pin;
-  ScopedComPtr<IEnumPins> pin_emum;
-  HRESULT hr = filter->EnumPins(pin_emum.Receive());
-  if (pin_emum == NULL)
+  ScopedComPtr<IEnumPins> pin_enum;
+  HRESULT hr = filter->EnumPins(pin_enum.Receive());
+  if (pin_enum == NULL)
     return pin;
 
   // Get first unconnected pin.
-  hr = pin_emum->Reset();  // set to first pin
-  while ((hr = pin_emum->Next(1, pin.Receive(), NULL)) == S_OK) {
+  hr = pin_enum->Reset();  // set to first pin
+  while ((hr = pin_enum->Next(1, pin.Receive(), NULL)) == S_OK) {
     PIN_DIRECTION this_pin_dir = static_cast<PIN_DIRECTION>(-1);
     hr = pin->QueryDirection(&this_pin_dir);
     if (pin_dir == this_pin_dir) {
       if (category == GUID_NULL || PinMatchesCategory(pin, category))
         return pin;
     }
     pin.Release();
   }
 
   DCHECK(!pin);
@@ skipping 423 matching lines @@
   }
 }
 
 void VideoCaptureDeviceWin::SetErrorState(const std::string& reason) {
   DCHECK(CalledOnValidThread());
   DVLOG(1) << reason;
   state_ = kError;
   client_->OnError(reason);
 }
 }  // namespace media