Fix OfflinePageEvaluationBridge.java being included when native side is not

The native side (offline_page_evaluation_bridge.cc) is guarded by
enable_offline_pages_harness, while the java side is guarded by
is_official_build.

This change makes them both guarded only by enable_offline_pages_harness.

Bug: 683256
Change-Id: Iec020944b5a2bde349c0973b8666bf130beb135e
Reviewed-on: https://chromium-review.googlesource.com/526655
Commit-Queue: Yipeng Wang <[email protected]>
Reviewed-by: Yafei Duan <[email protected]>
Reviewed-by: Andrew Grieve <[email protected]>
Cr-Commit-Position: refs/heads/master@{#477703}
diff --git a/chrome/browser/BUILD.gn b/chrome/browser/BUILD.gn
index f01e9e4..33b1773 100644
--- a/chrome/browser/BUILD.gn
+++ b/chrome/browser/BUILD.gn
@@ -4343,7 +4343,7 @@
     ]
 
     # Used for testing only, should not be shipped to end users.
-    if (!is_official_build) {
+    if (enable_offline_pages_harness) {
       sources += [ "../android/java/src/org/chromium/chrome/browser/offlinepages/evaluation/OfflinePageEvaluationBridge.java" ]
     }
     jni_package = "chrome"