Remove static from http2metricschannelhandler to allow for override (#…

…1750)

* Remove static from http2metricschannelhandler to allow for override

* Update incrementErrorCounter function

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Co-authored-by: $(git --no-pager log --format=format:'%an' -n 1) <$(git --no-pager log --format=format:'%ae' -n 1)>

zuul-core/src/main/java/com/netflix/netty/common/metrics/Http2MetricsChannelHandlers.java

@@ -45,16 +45,15 @@ public Outbound outbound() {
         return outbound;
     }
 
-    protected static void incrementErrorCounter(
-            Registry registry, String counterName, String metricId, Http2Exception h2e) {
+    protected void incrementErrorCounter(Registry registry, String counterName, String metricId, Http2Exception h2e) {
         String h2Error = h2e.error() != null ? h2e.error().name() : "NA";
         String exceptionName = h2e.getClass().getSimpleName();
 
         registry.counter(counterName, "id", metricId, "error", h2Error, "exception", exceptionName)
                 .increment();
     }
 
-    protected static void incrementCounter(Registry registry, String counterName, String metricId, Http2Frame frame) {
+    protected void incrementCounter(Registry registry, String counterName, String metricId, Http2Frame frame) {
         long errorCode;
         if (frame instanceof Http2ResetFrame) {
             errorCode = ((Http2ResetFrame) frame).errorCode();
@@ -69,7 +68,7 @@ protected static void incrementCounter(Registry registry, String counterName, St
     }
 
     @ChannelHandler.Sharable
-    private static class Inbound extends ChannelInboundHandlerAdapter {
+    private class Inbound extends ChannelInboundHandlerAdapter {
         private final Registry registry;
         private final String metricId;
         private final String frameCounterName;
@@ -117,7 +116,7 @@ public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws E
     }
 
     @ChannelHandler.Sharable
-    private static class Outbound extends ChannelOutboundHandlerAdapter {
+    private class Outbound extends ChannelOutboundHandlerAdapter {
         private final Registry registry;
         private final String metricId;
         private final String frameCounterName;