Fix CreateObjectURL deprecation message.

Removal has been postponed to M71.

Bug: 800767
Change-Id: I73c3ab4b25ac3856398a639cfb8d5c08fe9aa7cc
Reviewed-on: https://chromium-review.googlesource.com/1172283Reviewed-by: Florent Castelli <orphis@chromium.org>
Reviewed-by: Philip Jägenstedt <foolip@chromium.org>
Commit-Queue: Guido Urdaneta <guidou@chromium.org>
Cr-Commit-Position: refs/heads/master@{#582710}

third_party/blink/renderer/core/frame/deprecation.cc

@@ -501,9 +501,9 @@ DeprecationInfo GetDeprecationInfo(WebFeature feature) {
                      "in a `.css` file extension.")};
 
     case WebFeature::kCreateObjectURLMediaStream:
-      return {"CreateObjectURLMediaStreamDeprecated", kM69,
+      return {"CreateObjectURLMediaStreamDeprecated", kM71,
               ReplacedWillBeRemoved("URL.createObjectURL with media streams",
-                                    "HTMLMediaElement.srcObject", kM69,
+                                    "HTMLMediaElement.srcObject", kM71,
                                     "5618491470118912")};
 
     case WebFeature::kChromeLoadTimesRequestTime: