Removing flow modification during sink/source addition/removal.

Changes:
- fwd objectives are pushed only the first time for a given device
- fwd objectives are removed only if the dev is no more serving the group
- mac/vlan filt objectives are pushed only the first time for a given device
- vlan filt objectives are pushed only the first time for a given cpoint
- filt objectives are purged upon device, link and edge port failures
- adds sr-filt-mcast to dump the installed filt obj
- updates onos-diags

Change-Id: I802ebec7e160486fea9ad4bf53aca36a2b1c7146
diff --git a/app/src/main/java/org/onosproject/segmentrouting/mcast/McastFilteringObjStoreKey.java b/app/src/main/java/org/onosproject/segmentrouting/mcast/McastFilteringObjStoreKey.java
new file mode 100644
index 0000000..6d69984
--- /dev/null
+++ b/app/src/main/java/org/onosproject/segmentrouting/mcast/McastFilteringObjStoreKey.java
@@ -0,0 +1,114 @@
+/*
+ * Copyright 2018-present Open Networking Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.segmentrouting.mcast;
+
+import org.onlab.packet.VlanId;
+import org.onosproject.net.ConnectPoint;
+
+import java.util.Objects;
+
+import static com.google.common.base.MoreObjects.toStringHelper;
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * Key of multicast filtering objective store.
+ */
+public class McastFilteringObjStoreKey {
+
+    private final ConnectPoint ingressCP;
+    private final VlanId vlanId;
+    private final boolean isIpv4;
+
+    /**
+     * Constructs the key of multicast filtering objective store.
+     *
+     * @param ingressCP ingress ConnectPoint
+     * @param vlanId vlan id
+     * @param isIpv4 is Ipv4
+     */
+    public McastFilteringObjStoreKey(ConnectPoint ingressCP, VlanId vlanId, boolean isIpv4) {
+        checkNotNull(ingressCP, "connectpoint cannot be null");
+        checkNotNull(vlanId, "vlanid cannot be null");
+        this.ingressCP = ingressCP;
+        this.vlanId = vlanId;
+        this.isIpv4 = isIpv4;
+    }
+
+    // Constructor for serialization
+    private McastFilteringObjStoreKey() {
+        this.ingressCP = null;
+        this.vlanId = null;
+        this.isIpv4 = false;
+    }
+
+
+    /**
+     * Returns the connect point.
+     *
+     * @return ingress connectpoint
+     */
+    public ConnectPoint ingressCP() {
+        return ingressCP;
+    }
+
+    /**
+     * Returns whether the filtering is for ipv4 mcast.
+     *
+     * @return isIpv4
+     */
+    public boolean isIpv4() {
+        return isIpv4;
+    }
+
+    /**
+     * Returns the vlan ID of this key.
+     *
+     * @return vlan ID
+     */
+    public VlanId vlanId() {
+        return vlanId;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) {
+            return true;
+        }
+        if (!(o instanceof McastFilteringObjStoreKey)) {
+            return false;
+        }
+        McastFilteringObjStoreKey that =
+                (McastFilteringObjStoreKey) o;
+        return (Objects.equals(this.ingressCP, that.ingressCP) &&
+                Objects.equals(this.isIpv4, that.isIpv4) &&
+                Objects.equals(this.vlanId, that.vlanId));
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(ingressCP, vlanId, isIpv4);
+    }
+
+    @Override
+    public String toString() {
+        return toStringHelper(getClass())
+                .add("ingressCP", ingressCP)
+                .add("isIpv4", isIpv4)
+                .add("vlanId", vlanId)
+                .toString();
+    }
+}