Add empty setWebContentsDebuggingEnabled implementation

Temporary patch to keep master building. This should be reverted when
the next master-chromium merge containing crrev.com/224607 and
go/ag/361664 have been rolled in.

Change-Id: I2cf15c05552a64b7f24b4d19b2faeeb382810763
diff --git a/chromium/java/com/android/webview/chromium/WebViewChromiumFactoryProvider.java b/chromium/java/com/android/webview/chromium/WebViewChromiumFactoryProvider.java
index 2324d31..14c86d9 100644
--- a/chromium/java/com/android/webview/chromium/WebViewChromiumFactoryProvider.java
+++ b/chromium/java/com/android/webview/chromium/WebViewChromiumFactoryProvider.java
@@ -199,6 +199,10 @@
                                     ComponentCallbacks2.TRIM_MEMORY_COMPLETE);
                         }
                     }
+
+                    // TODO: replace with real implementation on next master-chromium merge.
+                    public void setWebContentsDebuggingEnabled(boolean enable) {
+                    }
                 };
             }
         }