Add new gpu driver bug workaround DISABLE_TRANSPARENT_VISUALS

ui/views/widget/widget_unittest.cc

Index: ui/views/widget/widget_unittest.cc
diff --git a/ui/views/widget/widget_unittest.cc b/ui/views/widget/widget_unittest.cc
index 45ea028344667104e55aa80eee54da1c9e167e1a..d3671da0945e4611710bcc5bb48b49dc351f2145 100644
--- a/ui/views/widget/widget_unittest.cc
+++ b/ui/views/widget/widget_unittest.cc
@@ -7,7 +7,7 @@
 #include <set>
 
 #include "base/bind.h"
-#include "base/command_line.h"
+#include "base/environment.h"
 #include "base/macros.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
@@ -3744,13 +3744,14 @@ void InitializeWidgetForOpacity(
     Widget::InitParams init_params,
     const Widget::InitParams::WindowOpacity opacity) {
 #if defined(USE_X11)
-  // On Linux, transparent visuals is currently not activated by default.
-  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
-  command_line->AppendSwitch(switches::kEnableTransparentVisuals);
-
+  // testing/xvfb.py runs xvfb and xcompmgr.
+  std::unique_ptr<base::Environment> env(base::Environment::Create());
+  bool has_compositing_manager = env->HasVar("_CHROMIUM_INSIDE_XVFB");

[Ken Russell (switch to Gerrit), 2016/07/06 22:32:17]

This is a hack. Is there no better way to determine whether to try transparent
visuals?

[Julien Isorce Samsung, 2016/07/07 10:29:23]

The idea here is to only do EXPECT_EQ(depth, 32); if the test is ran under
src/testing/xvfb.py because now this script also starts a compositing manager
named xcompmgr. And I have not found a better to check that the test is ran
within this script. In any other configuration the test should not assert there,
for example it will fails with nvidia proprietary drivers if the driver contains
that bug.

   int depth = 0;
-  ui::ChooseVisualForWindow(NULL, &depth);
-  EXPECT_EQ(depth, 32);
+  ui::ChooseVisualForWindow(!has_compositing_manager, NULL, &depth);
+
+  if (has_compositing_manager)
+    EXPECT_EQ(depth, 32);
 #endif
 
   init_params.opacity = opacity;
@@ -3762,7 +3763,8 @@ void InitializeWidgetForOpacity(
   widget.Init(init_params);
 
 #if defined(USE_X11)
-  EXPECT_TRUE(widget.IsTranslucentWindowOpacitySupported());
+  if (has_compositing_manager)
+    EXPECT_TRUE(widget.IsTranslucentWindowOpacitySupported());
 #endif
 }