problem: in some cases WS may produce empty or broken messages that breaks the connection

solution: better handling for invalid JSON

(cherry picked from commit 1b6a995c4e746f0704643426fc20f7496fc09cef)

src/test/groovy/io/emeraldpay/dshackle/upstream/rpcclient/ResponseRpcParserSpec.groovy

@@ -223,4 +223,27 @@ class ResponseRpcParserSpec extends Specification {
         !act.hasResult()
     }
 
+    def "Keep provided ID even if JSON is not full"() {
+        setup:
+        def json = '{"jsonrpc": "2.0", "id": 1}'
+        when:
+        def act = parser.parse(json.getBytes())
+        then:
+        act.id.asNumber() == 1
+        act.error != null
+        act.hasError()
+        !act.hasResult()
+    }
+
+    def "Keep provided ID even if JSON is broken"() {
+        setup:
+        def json = '{"jsonrpc": "2.0", "id": 101, "resu'
+        when:
+        def act = parser.parse(json.getBytes())
+        then:
+        act.id.asNumber() == 101
+        act.error != null
+        act.hasError()
+        !act.hasResult()
+    }
 }

src/test/groovy/io/emeraldpay/dshackle/upstream/rpcclient/ResponseWSParserSpec.groovy

@@ -103,4 +103,24 @@ class ResponseWSParserSpec extends Specification {
         act.error == null
         new String(act.value) == "null"
     }
+
+    def "Keep provided ID even if JSON is not full"() {
+        setup:
+        def json = '{"jsonrpc": "2.0", "id": 1}'
+        when:
+        def act = parser.parse(json.getBytes())
+        then:
+        act.id.asNumber() == 1
+        act.error != null
+    }
+
+    def "Keep provided ID even if JSON is broken"() {
+        setup:
+        def json = '{"jsonrpc": "2.0", "id": 101, "resu'
+        when:
+        def act = parser.parse(json.getBytes())
+        then:
+        act.id.asNumber() == 101
+        act.error != null
+    }
 }