Set the WM_CLASS property of X11 windows in Linux Aura build.

ui/base/x/x11_util.cc

Index: ui/base/x/x11_util.cc
diff --git a/ui/base/x/x11_util.cc b/ui/base/x/x11_util.cc
index 3a1ced1533fdda64690c1eeec798df6346d03a95..44d8d2885a131d92e2c438062a9d1ff4b1eec054 100644
--- a/ui/base/x/x11_util.cc
+++ b/ui/base/x/x11_util.cc
@@ -1012,6 +1012,19 @@ Atom GetAtom(const char* name) {
 #endif
 }
 
+void SetWindowClassHint(Display* display,
+                        XID window,
+                        std::string res_name,
+                        std::string res_class) {
+  XClassHint class_hints;
+  // const_cast is safe because XSetClassHint does not modify the strings.
+  // Just to be safe, the res_name and res_class parameters are local copies,
+  // not const references.
+  class_hints.res_name = const_cast<char*>(res_name.c_str());
+  class_hints.res_class = const_cast<char*>(res_class.c_str());
+  XSetClassHint(display, window, &class_hints);
+}
+
 XID GetParentWindow(XID window) {
   XID root = None;
   XID parent = None;