gpu: Support parallel active queries in command buffer

gpu/command_buffer/tests/gl_query_unittests.cc

Index: gpu/command_buffer/tests/gl_query_unittests.cc
diff --git a/gpu/command_buffer/tests/gl_query_unittests.cc b/gpu/command_buffer/tests/gl_query_unittests.cc
index 4d1700d847c673a7b9ff55866d895b8fda36dd29..b2dcc6b831c617699935f6eae3e3bebadf32a6c5 100644
--- a/gpu/command_buffer/tests/gl_query_unittests.cc
+++ b/gpu/command_buffer/tests/gl_query_unittests.cc
@@ -27,6 +27,50 @@ class QueryTest : public testing::Test {
   GLManager gl_;
 };
 
+TEST_F(QueryTest, MultipleQueries) {
+  EXPECT_TRUE(GLTestHelper::HasExtension("GL_CHROMIUM_get_error_query"));
+  EXPECT_TRUE(GLTestHelper::HasExtension(
+                  "GL_CHROMIUM_command_buffer_latency_query"));
+
+  GLuint error_query = 0;
+  GLuint latency_query = 0;
+  glGenQueriesEXT(1, &error_query);
+  glGenQueriesEXT(1, &latency_query);
+
+  GLuint query_status;
+  GLuint available;
+
+  // Begin two queries of different types
+  glBeginQueryEXT(GL_LATENCY_QUERY_CHROMIUM, latency_query);
+  glBeginQueryEXT(GL_GET_ERROR_QUERY_CHROMIUM, error_query);
+
+  glEnable(GL_TEXTURE_2D);  // Generates an INVALID_ENUM error
+
+  // End the two queries
+  glEndQueryEXT(GL_LATENCY_QUERY_CHROMIUM);
+  glEndQueryEXT(GL_GET_ERROR_QUERY_CHROMIUM);
+
+  glFinish();
+
+  // Check that we got result on both queries.
+
+  available = 0;
+  glGetQueryObjectuivEXT(latency_query,
+                         GL_QUERY_RESULT_AVAILABLE_EXT,
+                         &available);
+  EXPECT_TRUE(available);
+  // TODO(jadahl): Check latency result whenever latency test is enabled

[reveman, 2014/01/02 15:38:12]

Would it be better to use a GL_COMMANDS_ISSUED_CHROMIUM query here? That should
give us a result we can check.

+
+  query_status = 0;
+  available = 0;
+  glGetQueryObjectuivEXT(error_query,
+                         GL_QUERY_RESULT_AVAILABLE_EXT,
+                         &available);
+  EXPECT_TRUE(available);
+  glGetQueryObjectuivEXT(error_query, GL_QUERY_RESULT_EXT, &query_status);
+  EXPECT_EQ(static_cast<uint32>(GL_INVALID_ENUM), query_status);
+}
+
 TEST_F(QueryTest, GetErrorBasic) {
   EXPECT_TRUE(GLTestHelper::HasExtension("GL_CHROMIUM_get_error_query"));