Fix Eclipse warnings

- Statement unnecessarily nested in 'else' clause
- Missing @Override annotations
- Unnecessary 'unused' warning suppression

Change-Id: I388909d5eb517a0d657e1e5dc26f64800bd46caf

src/main/java/com/googlesource/gerrit/plugins/manager/GerritVersionBranch.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/manager/GerritVersionBranch.java b/src/main/java/com/googlesource/gerrit/plugins/manager/GerritVersionBranch.java
index 75256b2..faca388 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/manager/GerritVersionBranch.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/manager/GerritVersionBranch.java
@@ -22,21 +22,20 @@
         || !Character.isDigit(gerritVersion.trim().charAt(0))
         || gerritVersion.startsWith(GERRIT_NEXT_VERSION)) {
       return "master";
-    } else {
-      String[] versionNumbers = gerritVersion.split("\\.");
+    }
+    String[] versionNumbers = gerritVersion.split("\\.");
 
-      if (versionNumbers.length > 2) {
-        String fixVersionNumber = versionNumbers[2];
-        if (fixVersionNumber.contains("-")) {
-          String nextVersion =
-              String.format("%s.%d", versionNumbers[0],
-                  Integer.parseInt(versionNumbers[1]) + 1);
-          if (nextVersion.equals(GERRIT_NEXT_VERSION)) {
-            return "master";
-          }
+    if (versionNumbers.length > 2) {
+      String fixVersionNumber = versionNumbers[2];
+      if (fixVersionNumber.contains("-")) {
+        String nextVersion =
+            String.format("%s.%d", versionNumbers[0],
+                Integer.parseInt(versionNumbers[1]) + 1);
+        if (nextVersion.equals(GERRIT_NEXT_VERSION)) {
+          return "master";
         }
       }
-      return "stable-" + versionNumbers[0] + "." + versionNumbers[1];
     }
+    return "stable-" + versionNumbers[0] + "." + versionNumbers[1];
   }
 }

src/main/java/com/googlesource/gerrit/plugins/manager/TokenReplaceOutputStream.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/manager/TokenReplaceOutputStream.java b/src/main/java/com/googlesource/gerrit/plugins/manager/TokenReplaceOutputStream.java
index 2c5976b..4eb643b 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/manager/TokenReplaceOutputStream.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/manager/TokenReplaceOutputStream.java
@@ -97,9 +97,11 @@
     flush();
   }
 
-  public void setWriteListener(@SuppressWarnings("unused") WriteListener writeListener) {
+  @Override
+  public void setWriteListener(WriteListener writeListener) {
   }
 
+  @Override
   public boolean isReady() {
     return true;
   }

src/main/java/com/googlesource/gerrit/plugins/manager/gson/SmartJson.java

diff --git a/src/main/java/com/googlesource/gerrit/plugins/manager/gson/SmartJson.java b/src/main/java/com/googlesource/gerrit/plugins/manager/gson/SmartJson.java
index 7766796..ff0b96b 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/manager/gson/SmartJson.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/manager/gson/SmartJson.java
@@ -51,9 +51,8 @@
     if (jsonElem != null && jsonElem.getAsJsonObject().get(fieldName) != null) {
       return Optional.of(SmartJson
           .of(jsonElem.getAsJsonObject().get(fieldName)));
-    } else {
-      return Optional.absent();
     }
+    return Optional.absent();
   }
 
   public SmartJson get(String fieldName) {