Linux: Support the --class argument (Reland)

chrome/browser/shell_integration_linux.cc

Index: chrome/browser/shell_integration_linux.cc
diff --git a/chrome/browser/shell_integration_linux.cc b/chrome/browser/shell_integration_linux.cc
index 7e63e1dd943f06c7071f0bbffa990b6a4699728b..128bb132fc9004d9cbb58f1901c80dc7819dfa6a 100644
--- a/chrome/browser/shell_integration_linux.cc
+++ b/chrome/browser/shell_integration_linux.cc
@@ -208,6 +208,18 @@ DefaultWebClientState GetIsDefaultWebClient(const std::string& protocol) {
 #endif
 }
 
+// https://wiki.gnome.org/Projects/GnomeShell/ApplicationBased
+// The WM_CLASS property should be set to the same as the *.desktop file without
+// the .desktop extension.  We cannot simply use argv[0] in this case, because
+// on the stable channel, the executable name is google-chrome-stable, but the
+// desktop file is google-chrome.desktop.
+std::string GetDesktopBaseName(const std::string& desktop_file_name) {
+  std::size_t last = desktop_file_name.find(".desktop");

[Lei Zhang, 2016/07/28 21:28:46]

BTW, std::string::find() in the worst case has a much worse run time vs
base::EndsWith(). That's what we really want to check here, right?

[Tom (Use chromium acct), 2016/07/28 23:02:13]

Done.

+  if (last != std::string::npos)
+    return desktop_file_name.substr(0, last);
+  return desktop_file_name;
+}
+
 }  // namespace
 
 bool SetAsDefaultBrowser() {
@@ -576,13 +588,49 @@ std::vector<base::FilePath> GetDataSearchLocations(base::Environment* env) {
   return search_paths;
 }
 
+namespace internal {
+
+std::string GetProgramClassName(const base::CommandLine& command_line,
+                                const std::string& desktop_file_name) {
+  std::string class_name =
+      shell_integration::GetDesktopBaseName(desktop_file_name);
+  if (command_line.HasSwitch(switches::kUserDataDir)) {

[Lei Zhang, 2016/07/28 21:28:46]

I wouldn't bother with this. I'd just call command_line.GetSwitchValueNative()
and handle the non-empty case instead.

base::CommandLine will happily take --class  <-- no value! --> and then you'd
end up with "google-chrome()".

[Tom (Use chromium acct), 2016/07/28 23:02:13]

Done.

+    // Set the class name to e.g. "Chrome (/tmp/my-user-data)".  The
+    // class name will show up in the alt-tab list in gnome-shell if
+    // you're running a binary that doesn't have a matching .desktop
+    // file.
+    const std::string user_data_dir =
+        command_line.GetSwitchValueNative(switches::kUserDataDir);
+    class_name += " (" + user_data_dir + ")";
+  }
+  return class_name;
+}
+
+std::string GetProgramClassClass(const base::CommandLine& command_line,
+                                 const std::string& desktop_file_name) {
+  std::string class_class =

[Lei Zhang, 2016/07/28 21:28:46]

Call this after handling the switch?

[Tom (Use chromium acct), 2016/07/28 23:02:13]

Done.

+      shell_integration::GetDesktopBaseName(desktop_file_name);
+  if (command_line.HasSwitch(switches::kWmClass))
+    return command_line.GetSwitchValueASCII(switches::kWmClass);
+  if (!class_class.empty()) {
+    // Capitalize the first character like gtk does.
+    class_class[0] = base::ToUpperASCII(class_class[0]);
+  }
+  return class_class;
+}
+
+}  // namespace internal
+
 std::string GetProgramClassName() {
   std::unique_ptr<base::Environment> env(base::Environment::Create());
-  std::string desktop_file(GetDesktopName(env.get()));
-  std::size_t last = desktop_file.find(".desktop");
-  if (last != std::string::npos)
-    return desktop_file.substr(0, last);
-  return desktop_file;
+  return internal::GetProgramClassName(*base::CommandLine::ForCurrentProcess(),
+                                       GetDesktopName(env.get()));
+}
+
+std::string GetProgramClassClass() {
+  std::unique_ptr<base::Environment> env(base::Environment::Create());
+  return internal::GetProgramClassClass(*base::CommandLine::ForCurrentProcess(),
+                                        GetDesktopName(env.get()));
 }
 
 std::string GetDesktopName(base::Environment* env) {