Simplify Ampersand escaping logic in RenderViewContextMenu.

chrome/browser/tab_contents/render_view_context_menu.cc

Index: chrome/browser/tab_contents/render_view_context_menu.cc
diff --git a/chrome/browser/tab_contents/render_view_context_menu.cc b/chrome/browser/tab_contents/render_view_context_menu.cc
index fdc406fe5b69d11cb045c003061153e9474c9b6e..66e20a9d82e92ce55863f784b9d4005129996bf8 100644
--- a/chrome/browser/tab_contents/render_view_context_menu.cc
+++ b/chrome/browser/tab_contents/render_view_context_menu.cc
@@ -389,10 +389,8 @@ void RenderViewContextMenu::AppendAllExtensionItems() {
        i != sorted_ids.end(); ++i) {
     string16 printable_selection_text = PrintableSelectionText();
     // Escape "&" as "&&".
-    for (size_t position = printable_selection_text.find('&');
-         position != string16::npos;
-         position = printable_selection_text.find('&', position + 2))
-      printable_selection_text.insert(position, 1, '&');
+    ReplaceChars(printable_selection_text, ASCIIToUTF16("&").c_str(),

[Yoyo Zhou, 2013/02/19 18:34:01]

Try L"&" and L"&&" here.

[Joe Thomas, 2013/02/19 19:17:50]

This works only on platforms like windows where wchar_t is 2 bytes
(http://code.google.com/searchframe#OAMlx_jo-ck/src/base/string16.h&type=cs&l=35).

We get type conversion error on other platforms

[Joe Thomas, 2013/02/19 21:32:11]

Looks like my above explanation is not fully clear. Trying to explain it in a
better way.

ReplaceChars's second argument takes char16.  wchar_t takes 2 bytes on WINDOWS
but 4 bytes on POSIX platforms. And in WINDOWS wchar_t is typedef'ed to char16
(http://code.google.com/searchframe#OAMlx_jo-ck/src/base/string16.h&type=cs&l=35)

So using Unicode string directly compiles only on Windows but not on other
platforms as we lack suitable type conversion for unicode string to char16.

[Yoyo Zhou, 2013/02/19 21:57:02]

Bummer. I guess C++11 initializer lists would be really useful here if we could
use them inline.

The viable alternative I see is defining a helper function EscapeAmpersands, in
which you define

const char16 ampersand[] = {'&', 0};

What do you think about that?

[Joe Thomas, 2013/02/19 22:39:05]

That can be done. Patch updated.

+                 ASCIIToUTF16("&&"), &printable_selection_text);
 
     extension_items_.AppendExtensionItems(i->second, printable_selection_text,
                                           &index);
@@ -830,9 +828,9 @@ void RenderViewContextMenu::AppendSearchProvider() {
 
   string16 printable_selection_text = PrintableSelectionText();
   // Escape "&" as "&&".
-  for (size_t i = printable_selection_text.find('&'); i != string16::npos;
-       i = printable_selection_text.find('&', i + 2))
-    printable_selection_text.insert(i, 1, '&');
+  ReplaceChars(printable_selection_text, ASCIIToUTF16("&").c_str(),
+               ASCIIToUTF16("&&"), &printable_selection_text);
+
 
   if (AutocompleteMatch::IsSearchType(match.type)) {
     const TemplateURL* const default_provider =