Support for interactive set-chrome-as-default in Windows.

chrome/installer/util/shell_util.cc

Index: chrome/installer/util/shell_util.cc
diff --git a/chrome/installer/util/shell_util.cc b/chrome/installer/util/shell_util.cc
index ef7177ec96fb95b042d23b8defb0c757c4323347..3a0ac189e37ec99df9344f7c848375e4f08e5f4c 100644
--- a/chrome/installer/util/shell_util.cc
+++ b/chrome/installer/util/shell_util.cc
@@ -611,6 +611,22 @@ bool AnotherUserHasDefaultBrowser(BrowserDistribution* dist,
   return true;
 }
 
+// Launches the Windows 7 and Windows 8 dialog for picking the application to
+// handle the given protocol. Most importantly, this is used to set the default
+// handler for http (and, implicitly with it, https). In that case it is also
+// known as the 'how do you want to open webpages' dialog.
+bool LaunchSelectDefaultProtocolHandlerDialog(const wchar_t* protocol) {

[gab, 2012/06/06 22:47:21]

This method should either:
- RegisterChromeForProtocol with elevate_if_not_admin = true
(note that this also calls RegisterChromeBrowser so that no caller would have to
worry about registration :)... given this function is in ShellUtil this is a
perfect place to do registration imo)

or
- Enforce in its contract (i.e. comments) the |protocol| needs to already be
registered.
and enforce it with DCHECK(ShellUtil::IsChromeRegisteredForProtocol(...))

otherwise we risk popping the dialog and not have Chrome listed in it =(!

[grt (UTC plus 2), 2012/06/07 02:50:36]

Don't do this.  This is a small, private, easy to understand helper function
with a clear purpose.  Please keep it that way.

[gab, 2012/06/07 14:01:51]

Ok, but do add it to the contract then, right?

[motek., 2012/06/07 14:58:50]

Ack.

[motek., 2012/06/07 14:58:50]

Ack. But see below.

[motek., 2012/06/07 14:58:50]

Well, perhaps to comments. Enforcement through DCHECK seems spurious and would
require passing extra parameters JUST to make that DCHECK. Updated the comment. 

[gab, 2012/06/07 15:18:54]

Arg, indeed, for now, because you need to know the suffix... I'm adding code as
we speak to have a method to do this, ShellUtil::GetCurrentInstallationSuffix():
http://codereview.chromium.org/10451074/

I'm fine with no DCHECK for now then :(.

+  DCHECK(protocol);
+  OPENASINFO open_as_info = {};
+  open_as_info.pcszFile = protocol;
+  open_as_info.oaifInFlags =
+      OAIF_URL_PROTOCOL | OAIF_FORCE_REGISTRATION | OAIF_REGISTER_EXT;
+  HRESULT hr = SHOpenWithDialog(NULL, &open_as_info);
+  DLOG_IF(WARNING, FAILED(hr)) << "Failed to set as default http handler; hr=0x"

[gab, 2012/06/06 22:47:21]

"http" --> << protocol <<

[motek., 2012/06/07 14:58:50]

Done.

+      << std::hex << hr;

[gab, 2012/06/06 22:47:21]

I'm not exactly sure which osstream is used for DLOGS, but be warned that <<
std::hex << changes the output format for ALL future integers passed in this
stream!

So if the DLOG stream is some kind of global output stream you might be messing
up logs all over the place...

[grt (UTC plus 2), 2012/06/07 02:50:36]

The stream's lifetime is bound to the log message itself, which dies at the
semicolon.  This use of std::hex is safe.

[gab, 2012/06/07 15:18:54]

Awesome, good to know :).

+  return SUCCEEDED(hr);
+}
+
 // Launches the Windows 7 and Windows 8 application association dialog, which
 // is the only documented way to make a browser the default browser on
 // Windows 8.
@@ -945,6 +961,14 @@ bool ShellUtil::MakeChromeDefault(BrowserDistribution* dist,
   if (!dist->CanSetAsDefault())
     return false;
 
+  // Windows 8 does not permit making a browser default just like that.
+  // This process needs to be routed through the system's UI. Use
+  // ShowMakeChromeDefaultSystemUI instead (below).
+  if (base::win::GetVersion() >= base::win::VERSION_WIN8) {
+    NOTREACHED();
+    return false;
+  }
+
   ShellUtil::RegisterChromeBrowser(dist, chrome_exe, L"", elevate_if_not_admin);
 
   bool ret = true;
@@ -955,17 +979,7 @@ bool ShellUtil::MakeChromeDefault(BrowserDistribution* dist,
   if (ShellUtil::GetUserSpecificDefaultBrowserSuffix(dist, &app_suffix))
     app_name += app_suffix;
 
-  if (base::win::GetVersion() >= base::win::VERSION_WIN8) {
-    // On Windows 8, you can't set yourself as the default handler
-    // programatically. In other words IApplicationAssociationRegistration
-    // has been rendered useless. What you can do is to launch
-    // "Set Program Associations" section of the "Default Programs"
-    // control panel. This action does not require elevation and we
-    // don't get to control window activation. More info at:
-    // http://msdn.microsoft.com/en-us/library/cc144154(VS.85).aspx
-    return LaunchApplicationAssociationDialog(app_name.c_str());
-
-  } else if (base::win::GetVersion() >= base::win::VERSION_VISTA) {
+  if (base::win::GetVersion() >= base::win::VERSION_VISTA) {
     // On Windows Vista and Win7 we still can set ourselves via the
     // the IApplicationAssociationRegistration interface.
     VLOG(1) << "Registering Chrome as default browser on Vista.";
@@ -1027,6 +1041,24 @@ bool ShellUtil::MakeChromeDefault(BrowserDistribution* dist,
   return ret;
 }
 
+bool ShellUtil::ShowMakeChromeDefaultSystemUI(BrowserDistribution* dist,
+                                              const string16& chrome_exe) {
+  DCHECK_GE(base::win::GetVersion(), base::win::VERSION_WIN8);
+  if (!dist->CanSetAsDefault())
+    return false;
+
+  if (!RegisterChromeBrowser(dist, chrome_exe, string16(), true))
+      return false;
+
+  // On Windows 8, you can't set yourself as the default handler
+  // programatically. In other words IApplicationAssociationRegistration
+  // has been rendered useless. What you can do is to launch
+  // "Set Program Associations" section of the "Default Programs"
+  // control panel, which is a mess, or pop the concise "How you want to open
+  // webpages"? dialog.  We choose the latter.

[gab, 2012/06/06 22:47:21]

The '?' goes inside the quotes right?

[gab, 2012/06/06 22:47:21]

choose --> chose (i.e. chose is the past tense of choose).

[grt (UTC plus 2), 2012/06/07 02:50:36]

Dunno.  It sounds fine to me as-is.

[motek., 2012/06/07 14:58:50]

Done.

[motek., 2012/06/07 14:58:50]

This is as intended. I find the present tense to be perfectly natural in this
context. 

[motek., 2012/06/07 14:58:50]

Ack.

+  return LaunchSelectDefaultProtocolHandlerDialog(L"http");
+}
+
 bool ShellUtil::MakeChromeDefaultProtocolClient(BrowserDistribution* dist,
                                                 const string16& chrome_exe,
                                                 const string16& protocol) {