Remove deprecated WebClipboard::readHTML method.

ui/base/clipboard/clipboard_win.cc

 // Copyright (c) 2011 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.
 
 // Many of these functions are based on those found in
 // webkit/port/platform/PasteboardWin.cpp
 
 #include "ui/base/clipboard/clipboard.h"
 
 #include <shlobj.h>
@@ skipping 435 matching lines @@
     return;
 
   std::string cf_html(static_cast<const char*>(::GlobalLock(data)));
   ::GlobalUnlock(data);
 
   size_t html_start = std::string::npos;
   size_t start_index = std::string::npos;
   size_t end_index = std::string::npos;
   ClipboardUtil::CFHtmlExtractMetadata(cf_html, src_url, &html_start,
                                        &start_index, &end_index);
-  if (markup) {
-    // Some sanity checks...
-    DCHECK(start_index != std::string::npos);
-    DCHECK(end_index != std::string::npos);
-    DCHECK((start_index - html_start) <= kuint32max);
-    DCHECK((end_index - html_start) <= kuint32max);
 
-    markup->assign(UTF8ToWide(cf_html.data() + html_start));
-    *fragment_start = static_cast<uint32>(start_index - html_start);
-    *fragment_end = static_cast<uint32>(end_index - html_start);
-  }
+  // This might happen if the contents of the clipboard changed and CF_HTML is
+  // no longer available.
+  if (start_index == std::string::npos ||
+      end_index == std::string::npos ||
+      html_start == std::string::npos)
+    return;
+
+  DCHECK(start_index - html_start >= 0);
+  DCHECK(end_index - html_start >= 0);
+  DCHECK((start_index - html_start) <= kuint32max);
+  DCHECK((end_index - html_start) <= kuint32max);
+
+  markup->assign(UTF8ToWide(cf_html.data() + html_start));
+  *fragment_start = static_cast<uint32>(start_index - html_start);
+  *fragment_end = static_cast<uint32>(end_index - html_start);
 }
 
 SkBitmap Clipboard::ReadImage(Buffer buffer) const {
   DCHECK_EQ(buffer, BUFFER_STANDARD);
 
   // Acquire the clipboard.
   ScopedClipboard clipboard;
   if (!clipboard.Acquire(GetClipboardWindow()))
     return SkBitmap();
 
@@ skipping 254 matching lines @@
     clipboard_owner_ = ::CreateWindow(L"ClipboardOwnerWindowClass",
                                       L"ClipboardOwnerWindow",
                                       0, 0, 0, 0, 0,
                                       HWND_MESSAGE,
                                       0, 0, 0);
   }
   return clipboard_owner_;
 }
 
 }  // namespace ui