HookArgs: Add @CanonicalWebUrl annotation to urlProvider

In change I56fa559d3 the injection of urlProvider was moved from
HookFactory to HooksArgs, but the @CanonicalWebUrl was accidentally
omitted. This results in an empty string always being provided.

Bug: Issue 9262
Change-Id: I143855e84cba09fea2d1cb57e3e958e1ffd5abba

src/main/java/com/googlesource/gerrit/plugins/hooks/HookArgs.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/hooks/HookArgs.java b/src/main/java/com/googlesource/gerrit/plugins/hooks/HookArgs.java
index 12e42ec..91d3696 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/hooks/HookArgs.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/hooks/HookArgs.java
@@ -18,11 +18,13 @@
 
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
+import com.google.gerrit.common.Nullable;
 import com.google.gerrit.extensions.common.AccountInfo;
 import com.google.gerrit.extensions.common.ApprovalInfo;
 import com.google.gerrit.extensions.common.ChangeInfo;
 import com.google.gerrit.reviewdb.client.Account;
 import com.google.gerrit.server.IdentifiedUser;
+import com.google.gerrit.server.config.CanonicalWebUrl;
 import com.google.gerrit.server.config.SitePaths;
 import com.google.gerrit.server.git.GitRepositoryManager;
 import com.google.inject.Inject;
@@ -47,7 +49,7 @@
   @Inject
   HookArgs(
       IdentifiedUser.GenericFactory identifiedUserFactory,
-      Provider<String> urlProvider,
+      @CanonicalWebUrl @Nullable Provider<String> urlProvider,
       HookMetrics metrics,
       GitRepositoryManager gitManager,
       SitePaths sitePaths) {