Fix possible Strictmode crash when initializing non-presenting GVR context.

chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java

Index: chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
index 777990dbddc45e396757af2cf842843b94fa8125..c7dc2fed28379fe82365f41de413a1923fac2417 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/vr_shell/VrShellImpl.java
@@ -464,8 +464,8 @@ public class VrShellImpl
     public void onResume() {
         super.onResume();
         if (mNativeVrShell != 0) {
-            // Refreshing the viewer profile accesses disk, so we need to temporarily allow disk
-            // reads. The GVR team promises this will be fixed when they launch.
+            // Refreshing the viewer profile may accesses disk under some circumstances outside of
+            // our control.
             StrictMode.ThreadPolicy oldPolicy = StrictMode.allowThreadDiskReads();
             try {
                 nativeOnResume(mNativeVrShell);