Implement RemovableDeviceNotifications for Mac

base/sys_string_conversions_mac.mm

Index: base/sys_string_conversions_mac.mm
diff --git a/base/sys_string_conversions_mac.mm b/base/sys_string_conversions_mac.mm
index d1e37432f92eac06cdd9e1fb224006313ef4573a..97c796974e65ddf5ab1834c6b28b9b150ffe249a 100644
--- a/base/sys_string_conversions_mac.mm
+++ b/base/sys_string_conversions_mac.mm
@@ -163,11 +163,15 @@ NSString* SysUTF16ToNSString(const string16& utf16) {
 }
 
 std::string SysCFStringRefToUTF8(CFStringRef ref) {
+  if (!ref)

[Mark Mentovai, 2012/09/12 21:05:15]

This intentionally does not operate on NULL input for safe round-tripping. You
should adjust the caller instead of this.

[sail, 2012/09/12 22:38:26]

Done.
(I'm not sure I understand this.  Round-tripping would imply
SysUTF8ToCFString(NULL) returning NULL. But we're using references.)

[Mark Mentovai, 2012/09/12 22:45:26]

sail wrote:
Right, and there’s no such thing as a NULL reference, so this function should
crash as any other function that operates on CFStrings would upon encountering a
NULL CFString.

There’s already a way to represent an empty CFString, and it’s not NULL.
UTF8ToCFString(CFStringToUTF8(x)) == x, but as you modified this function
previously, that’s not the case for NULL. Since you can’t express a NULL object
(as opposed to a pointer), the correct thing to do is crash.

+    return std::string();
   return CFStringToSTLStringWithEncodingT<std::string>(ref,
                                                        kNarrowStringEncoding);
 }
 
 string16 SysCFStringRefToUTF16(CFStringRef ref) {
+  if (!ref)
+    return string16();
   return CFStringToSTLStringWithEncodingT<string16>(ref,
                                                     kMediumStringEncoding);
 }