Pepper: Fix nullptr crash in PepperWebPluginImpl::updateGeometry.

content/renderer/pepper/pepper_webplugin_impl.cc

Index: content/renderer/pepper/pepper_webplugin_impl.cc
diff --git a/content/renderer/pepper/pepper_webplugin_impl.cc b/content/renderer/pepper/pepper_webplugin_impl.cc
index 0caa190b0461432f89bd11635f5dde6646099123..25b96337996d6b0704e3a1822aad1ff16334469c 100644
--- a/content/renderer/pepper/pepper_webplugin_impl.cc
+++ b/content/renderer/pepper/pepper_webplugin_impl.cc
@@ -174,7 +174,7 @@ void PepperWebPluginImpl::updateGeometry(
     const WebVector<WebRect>& cut_outs_rects,
     bool is_visible) {
   plugin_rect_ = window_rect;
-  if (!instance_->FlashIsFullscreenOrPending()) {
+  if (instance_ && !instance_->FlashIsFullscreenOrPending()) {
     std::vector<gfx::Rect> cut_outs;
     for (size_t i = 0; i < cut_outs_rects.size(); ++i)
       cut_outs.push_back(cut_outs_rects[i]);