Don't show 'Add Me' button for change owner or existing reviewers

Change-Id: Ib79bd18d863b7b62e90be7179d85465f25cc7759

gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Reviewers.java

diff --git a/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Reviewers.java b/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Reviewers.java
index 10a140d..87320b8 100644
--- a/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Reviewers.java
+++ b/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Reviewers.java
@@ -65,6 +65,7 @@
 
   @UiField Element reviewersText;
   @UiField Button openForm;
+  @UiField Button addMe;
   @UiField Element form;
   @UiField Element error;
   @UiField(provided = true)
@@ -146,7 +147,7 @@
     }
   }
 
-  @UiHandler("addme")
+  @UiHandler("addMe")
   void onAddMe(ClickEvent e) {
     String accountId = String.valueOf(Gerrit.getUserAccountInfo()._account_id());
     addReviewer(accountId, false);
@@ -248,6 +249,13 @@
 
     reviewersText.setInnerSafeHtml(rHtml);
     ccText.setInnerSafeHtml(ccHtml);
+    if (Gerrit.isSignedIn()) {
+      int currentUser = Gerrit.getUserAccountInfo()._account_id();
+      boolean showAddMeButton = info.owner()._account_id() != currentUser
+          && !cc.containsKey(currentUser)
+          && !r.containsKey(currentUser);
+      addMe.setVisible(showAddMeButton);
+    }
   }
 
   private static Map<Integer, VotableInfo> votable(ChangeInfo change) {

gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Reviewers.ui.xml

diff --git a/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Reviewers.ui.xml b/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Reviewers.ui.xml
index 4e3b0c6..024197d 100644
--- a/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Reviewers.ui.xml
+++ b/gerrit-gwtui/src/main/java/com/google/gerrit/client/change/Reviewers.ui.xml
@@ -72,7 +72,8 @@
         <g:Button ui:field='add' styleName='{res.style.button}'>
           <div>Add</div>
         </g:Button>
-        <g:Button ui:field='addme' styleName='{res.style.button}'>
+        <g:Button ui:field='addMe'
+            styleName='{res.style.button}' visible='false'>
           <div>Add Me</div>
         </g:Button>
         <g:Button ui:field='cancel'