Update from https://crrev.com/315085

ui/gl/gl_fence_egl.cc

Index: ui/gl/gl_fence_egl.cc
diff --git a/ui/gl/gl_fence_egl.cc b/ui/gl/gl_fence_egl.cc
index c96d6d8157dea1b5c9c5f1915e6149d5379ca316..74f0a0171b6907a7b2943328af25e2360826070f 100644
--- a/ui/gl/gl_fence_egl.cc
+++ b/ui/gl/gl_fence_egl.cc
@@ -6,19 +6,25 @@
 
 #include "ui/gl/egl_util.h"
 #include "ui/gl/gl_bindings.h"
-#include "ui/gl/gl_context.h"
 
 namespace gfx {
 
-GLFenceEGL::GLFenceEGL(bool flush) {
+namespace {
+
+bool g_ignore_egl_sync_failures = false;
+
+}  // namespace
+
+// static
+void GLFenceEGL::SetIgnoreFailures() {
+  g_ignore_egl_sync_failures = true;
+}
+
+GLFenceEGL::GLFenceEGL() {
   display_ = eglGetCurrentDisplay();
   sync_ = eglCreateSyncKHR(display_, EGL_SYNC_FENCE_KHR, NULL);
   DCHECK(sync_ != EGL_NO_SYNC_KHR);
-  if (flush) {
-    glFlush();
-  } else {
-    flush_event_ = GLContext::GetCurrent()->SignalFlush();
-  }
+  glFlush();
 }
 
 bool GLFenceEGL::HasCompleted() {
@@ -35,17 +41,15 @@ bool GLFenceEGL::HasCompleted() {
 }
 
 void GLFenceEGL::ClientWait() {
-  if (!flush_event_.get() || flush_event_->IsSignaled()) {
-    EGLint flags = 0;
-    EGLTimeKHR time = EGL_FOREVER_KHR;
-    EGLint result = eglClientWaitSyncKHR(display_, sync_, flags, time);
-    DCHECK_NE(EGL_TIMEOUT_EXPIRED_KHR, result);
-    if (result == EGL_FALSE) {
-      LOG(FATAL) << "Failed to wait for EGLSync. error:"
-                 << ui::GetLastEGLErrorString();
-    }
-  } else {
-    LOG(ERROR) << "Trying to wait for uncommitted fence. Skipping...";
+  EGLint flags = 0;
+  EGLTimeKHR time = EGL_FOREVER_KHR;
+  EGLint result = eglClientWaitSyncKHR(display_, sync_, flags, time);
+  DCHECK_IMPLIES(!g_ignore_egl_sync_failures,
+                 EGL_TIMEOUT_EXPIRED_KHR == result);
+  if (result == EGL_FALSE) {
+    LOG(ERROR) << "Failed to wait for EGLSync. error:"
+               << ui::GetLastEGLErrorString();
+    CHECK(g_ignore_egl_sync_failures);
   }
 }
 
@@ -54,14 +58,11 @@ void GLFenceEGL::ServerWait() {
     ClientWait();
     return;
   }
-  if (!flush_event_.get() || flush_event_->IsSignaled()) {
-    EGLint flags = 0;
-    if (eglWaitSyncKHR(display_, sync_, flags) == EGL_FALSE) {
-      LOG(FATAL) << "Failed to wait for EGLSync. error:"
-                 << ui::GetLastEGLErrorString();
-    }
-  } else {
-    LOG(ERROR) << "Trying to wait for uncommitted fence. Skipping...";
+  EGLint flags = 0;
+  if (eglWaitSyncKHR(display_, sync_, flags) == EGL_FALSE) {
+    LOG(ERROR) << "Failed to wait for EGLSync. error:"
+               << ui::GetLastEGLErrorString();
+    CHECK(g_ignore_egl_sync_failures);
   }
 }