[FAB-3485] improve test coverage for msp/mgmt

Test output for msp/mgmt now is

coverage: 87.8% of statements
ok		github.com/hyperledger/fabric/msp/mgmt	0.033s

Change-Id: I6d34b9cf914d970b9a57de214cb4881c95fdbf13
Signed-off-by: Alessandro Sorniotti <ale.linux@sopit.net>

msp/mgmt/mgmt.go

@@ -113,15 +113,6 @@ func GetDeserializers() map[string]msp.IdentityDeserializer {
 	return clone
 }
 
-// GetManagerForChainIfExists returns the MSPManager associated to ChainID
-// it it exists
-func GetManagerForChainIfExists(ChainID string) msp.MSPManager {
-	m.Lock()
-	defer m.Unlock()
-
-	return mspMap[ChainID]
-}
-
 // XXXSetMSPManager is a stopgap solution to transition from the custom MSP config block
 // parsing to the configtx.Manager interface, while preserving the problematic singleton
 // nature of the MSP manager

msp/mgmt/mgmt_test.go

@@ -21,6 +21,7 @@ import (
 
 	configvaluesmsp "github.com/hyperledger/fabric/common/config/msp"
 	"github.com/hyperledger/fabric/msp"
+	"github.com/stretchr/testify/assert"
 )
 
 func TestGetManagerForChains(t *testing.T) {
@@ -54,3 +55,16 @@ func TestGetManagerForChains_usingMSPConfigHandlers(t *testing.T) {
 		t.FailNow()
 	}
 }
+
+func TestGetIdentityDeserializer(t *testing.T) {
+	XXXSetMSPManager("baz", &configvaluesmsp.MSPConfigHandler{MSPManager: msp.NewMSPManager()})
+	ids := GetIdentityDeserializer("baz")
+	assert.NotNil(t, ids)
+	ids = GetIdentityDeserializer("")
+	assert.NotNil(t, ids)
+}
+
+func TestGetLocalSigningIdentityOrPanic(t *testing.T) {
+	sid := GetLocalSigningIdentityOrPanic()
+	assert.NotNil(t, sid)
+}