Add WindowManager to about:gpu page on Linux/X11

BUG=410560
TEST=about:gpu page
R=piman@chromium.org,davemoore@chromium.org,sadrul@chromium.org,derat@chromium.org

Review URL: https://codereview.chromium.org/540643002

Cr-Commit-Position: refs/heads/master@{#293322}

content/browser/gpu/gpu_internals_ui.cc

@@ -34,6 +34,10 @@
 #include "ui/base/win/shell.h"
 #endif
 
+#if defined(OS_LINUX) && defined(USE_X11)
+#include "ui/base/x/x11_util.h"
+#endif
+
 namespace content {
 namespace {
 
@@ -161,6 +165,10 @@ base::DictionaryValue* GpuInfoAsDictionaryValue() {
                                              gpu_info.gl_ws_version));
   basic_info->Append(NewDescriptionValuePair("Window system binding extensions",
                                              gpu_info.gl_ws_extensions));
+#if defined(OS_LINUX) && defined(USE_X11)
+  basic_info->Append(NewDescriptionValuePair("Window manager",
+                                             ui::GuessWindowManagerName()));
+#endif
   std::string direct_rendering = gpu_info.direct_rendering ? "Yes" : "No";
   basic_info->Append(
       NewDescriptionValuePair("Direct rendering", direct_rendering));

ui/base/x/x11_util.cc

@@ -102,6 +102,38 @@ bool GetProperty(XID window, const std::string& property_name, long max_length,
                             property);
 }
 
+bool GetWindowManagerName(std::string* wm_name) {
+  DCHECK(wm_name);
+  int wm_window = 0;
+  if (!GetIntProperty(GetX11RootWindow(),
+                      "_NET_SUPPORTING_WM_CHECK",
+                      &wm_window)) {
+    return false;
+  }
+
+  // It's possible that a window manager started earlier in this X session left
+  // a stale _NET_SUPPORTING_WM_CHECK property when it was replaced by a
+  // non-EWMH window manager, so we trap errors in the following requests to
+  // avoid crashes (issue 23860).
+
+  // EWMH requires the supporting-WM window to also have a
+  // _NET_SUPPORTING_WM_CHECK property pointing to itself (to avoid a stale
+  // property referencing an ID that's been recycled for another window), so we
+  // check that too.
+  gfx::X11ErrorTracker err_tracker;
+  int wm_window_property = 0;
+  bool result = GetIntProperty(
+      wm_window, "_NET_SUPPORTING_WM_CHECK", &wm_window_property);
+  if (err_tracker.FoundNewError() || !result ||
+      wm_window_property != wm_window) {
+    return false;
+  }
+
+  result = GetStringProperty(
+      static_cast<XID>(wm_window), "_NET_WM_NAME", wm_name);
+  return !err_tracker.FoundNewError() && result;
+}
+
 // A process wide singleton that manages the usage of X cursors.
 class XCursorCache {
  public:
@@ -1155,38 +1187,6 @@ bool CopyAreaToCanvas(XID drawable,
   return true;
 }
 
-bool GetWindowManagerName(std::string* wm_name) {
-  DCHECK(wm_name);
-  int wm_window = 0;
-  if (!GetIntProperty(GetX11RootWindow(),
-                      "_NET_SUPPORTING_WM_CHECK",
-                      &wm_window)) {
-    return false;
-  }
-
-  // It's possible that a window manager started earlier in this X session left
-  // a stale _NET_SUPPORTING_WM_CHECK property when it was replaced by a
-  // non-EWMH window manager, so we trap errors in the following requests to
-  // avoid crashes (issue 23860).
-
-  // EWMH requires the supporting-WM window to also have a
-  // _NET_SUPPORTING_WM_CHECK property pointing to itself (to avoid a stale
-  // property referencing an ID that's been recycled for another window), so we
-  // check that too.
-  gfx::X11ErrorTracker err_tracker;
-  int wm_window_property = 0;
-  bool result = GetIntProperty(
-      wm_window, "_NET_SUPPORTING_WM_CHECK", &wm_window_property);
-  if (err_tracker.FoundNewError() || !result ||
-      wm_window_property != wm_window) {
-    return false;
-  }
-
-  result = GetStringProperty(
-      static_cast<XID>(wm_window), "_NET_WM_NAME", wm_name);
-  return !err_tracker.FoundNewError() && result;
-}
-
 WindowManagerName GuessWindowManager() {
   std::string name;
   if (GetWindowManagerName(&name)) {
@@ -1219,6 +1219,13 @@ WindowManagerName GuessWindowManager() {
   return WM_UNKNOWN;
 }
 
+std::string GuessWindowManagerName() {
+  std::string name;
+  if (GetWindowManagerName(&name))
+    return name;
+  return "Unknown";
+}
+
 void SetDefaultX11ErrorHandlers() {
   SetX11ErrorHandlers(NULL, NULL);
 }

ui/base/x/x11_util.h

@@ -262,6 +262,10 @@ enum WindowManagerName {
 // determine it for one reason or another.
 UI_BASE_EXPORT WindowManagerName GuessWindowManager();
 
+// The same as GuessWindowManager(), but returns the raw string.  If we
+// can't determine it, return "Unknown".
+UI_BASE_EXPORT std::string GuessWindowManagerName();
+
 // Enable the default X error handlers. These will log the error and abort
 // the process if called. Use SetX11ErrorHandlers() from x11_util_internal.h
 // to set your own error handlers.