Add build flag to control runtime annotator checks.

BUILD.gn

@@ -40,6 +40,9 @@ declare_args() {
   # Abseil has trouble supporting MSVC, particularly regarding component builds.
   # http://crbug.com/1126524
   angle_enable_abseil = angle_has_build && is_clang
+
+  # Adds run-time checks to filter out EVENT() messages when the debug annotator is disabled.
+  angle_enable_annotator_run_time_checks = false
 }
 
 if (angle_build_all) {
@@ -250,6 +253,9 @@ config("debug_annotations_config") {
   if (is_debug) {
     defines = [ "ANGLE_ENABLE_DEBUG_ANNOTATIONS" ]
   }
+  if (angle_enable_annotator_run_time_checks) {
+    defines = [ "ANGLE_ENABLE_ANNOTATOR_RUN_TIME_CHECKS" ]
+  }
 }
 
 config("angle_release_asserts_config") {

src/common/debug.cpp

@@ -89,6 +89,15 @@ bool DebugAnnotationsActive()
 #endif
 }
 
+bool ShouldBeginScopedEvent()
+{
+#if defined(ANGLE_ENABLE_ANNOTATOR_RUN_TIME_CHECKS)
+    return DebugAnnotationsActive();
+#else
+    return true;
+#endif  // defined(ANGLE_ENABLE_ANNOTATOR_RUN_TIME_CHECKS)
+}
+
 bool DebugAnnotationsInitialized()
 {
     return g_debugAnnotator != nullptr;
@@ -145,8 +154,10 @@ void ScopedPerfEventHelper::begin(const char *format, ...)
     va_end(vararg);
 
     ANGLE_LOG(EVENT) << std::string(&buffer[0], len);
-    // Do not need to call DebugAnnotationsActive() here, because it was called in EVENT()
-    g_debugAnnotator->beginEvent(mContext, mEntryPoint, mFunctionName, buffer.data());
+    if (DebugAnnotationsInitialized())
+    {
+        g_debugAnnotator->beginEvent(mContext, mEntryPoint, mFunctionName, buffer.data());
+    }
 }
 
 LogMessage::LogMessage(const char *file, const char *function, int line, LogSeverity severity)

src/common/debug.h

@@ -107,6 +107,7 @@ class DebugAnnotator : angle::NonCopyable
     virtual void logMessage(const LogMessage &msg) const = 0;
 };
 
+bool ShouldBeginScopedEvent();
 void InitializeDebugAnnotations(DebugAnnotator *debugAnnotator);
 void UninitializeDebugAnnotations();
 bool DebugAnnotationsActive();
@@ -259,7 +260,7 @@ std::ostream &FmtHex(std::ostream &os, T value)
             gl::ScopedPerfEventHelper scopedPerfEventHelper##__LINE__(context, entryPoint); \
             do                                                                              \
             {                                                                               \
-                if (gl::DebugAnnotationsActive())                                           \
+                if (gl::ShouldBeginScopedEvent())                                           \
                 {                                                                           \
                     scopedPerfEventHelper##__LINE__.begin("%s(" message ")", function,      \
                                                           __VA_ARGS__);                     \
@@ -270,7 +271,7 @@ std::ostream &FmtHex(std::ostream &os, T value)
             gl::ScopedPerfEventHelper scopedPerfEventHelper(context, entryPoint);            \
             do                                                                               \
             {                                                                                \
-                if (gl::DebugAnnotationsActive())                                            \
+                if (gl::ShouldBeginScopedEvent())                                            \
                 {                                                                            \
                     scopedPerfEventHelper.begin("%s(" message ")", function, ##__VA_ARGS__); \
                 }                                                                            \