Not implicitly set vol_device_name to vda

Using a scsi decorated image with:
hw_disk_bus='scsi'
hw_scsi_model='virtio-scsi'

This solve the case where an instance is
launched with 'image' selected as boot
source with a new volume. This will result
in /dev/vda instead of /dev/sda as it
should.

Not specifying device name in
setFinalSpecBootImageToVolume() leaves the
decision to nova to determine it.

Example:
-------
VM boot volume without scsi meta data decoration:
Attached To
0a0cd660-7ce3-4033-9983-2e1099edc5f0 on /dev/vda

VM boot volume with scsi meta data decoration:
Attached To
91f50dbc-8bdf-4293-84ea-fc5df27b5ee4 on /dev/sda
--------

Note: This commit doesn't address cases for
where instances are launched using existing
volume and snapshot, this will involve more
work to migrate the code from BDMv1 to BDMv2.

Closes-Bug #1560965

Change-Id: I9d114c2c2e6736a8f1a8092afa568f930b656f09
(cherry picked from commit 79a4c3bd1a)

openstack_dashboard/dashboards/project/static/dashboard/project/workflow/launch-instance/launch-instance-model.service.js

@@ -735,11 +735,9 @@
     function setFinalSpecBootImageToVolume(finalSpec) {
       if (finalSpec.vol_create) {
         // Specify null to get Autoselection (not empty string)
-        var deviceName = finalSpec.vol_device_name ? finalSpec.vol_device_name : null;
         finalSpec.block_device_mapping_v2 = [];
         finalSpec.block_device_mapping_v2.push(
           {
-            'device_name': deviceName,
             'source_type': bootSourceTypes.IMAGE,
             'destination_type': bootSourceTypes.VOLUME,
             'delete_on_termination': finalSpec.vol_delete_on_instance_delete,

openstack_dashboard/dashboards/project/static/dashboard/project/workflow/launch-instance/launch-instance-model.service.spec.js

@@ -895,7 +895,6 @@
 
         it('sets volume options appropriately', function() {
           expect(model.newInstanceSpec.vol_create).toBe(false);
-          expect(model.newInstanceSpec.vol_device_name).toBe('vda');
           expect(model.newInstanceSpec.vol_delete_on_instance_delete).toBe(false);
           expect(model.newInstanceSpec.vol_size).toBe(1);
         });
@@ -918,7 +917,6 @@
           model.newInstanceSpec.scheduler_hints = {};
           model.newInstanceSpec.vol_create = true;
           model.newInstanceSpec.vol_delete_on_instance_delete = true;
-          model.newInstanceSpec.vol_device_name = "volTestName";
           model.newInstanceSpec.vol_size = 10;
           model.newInstanceSpec.server_groups = [];
 
@@ -954,7 +952,6 @@
         it('should set final spec in format required for Block Device Mapping v2', function() {
           var finalSpec = model.createInstance();
           var expectedBlockDevice = [{
-            device_name: 'volTestName',
             source_type: 'image',
             destination_type: 'volume',
             delete_on_termination: true,
@@ -986,8 +983,6 @@
           model.newInstanceSpec.vol_delete_on_instance_delete = 'yep';
 
           var finalSpec = model.createInstance();
-          expect(finalSpec.block_device_mapping.volTestName)
-            .toBe('imAnID:vol::yep');
           expect(finalSpec.source_id).toBe('');
         });
 
@@ -997,7 +992,6 @@
 
           var finalSpec = model.createInstance();
           var expectedBlockDevice = [{
-            device_name: 'volTestName',
             source_type: 'image',
             destination_type: 'volume',
             delete_on_termination: true,
@@ -1015,8 +1009,6 @@
           model.newInstanceSpec.vol_delete_on_instance_delete = 'yep';
 
           var finalSpec = model.createInstance();
-          expect(finalSpec.block_device_mapping.volTestName)
-            .toBe('imAnID:snap::yep');
           expect(finalSpec.source_id).toBe('');
         });
 
@@ -1073,15 +1065,6 @@
           expect(finalSpec.nics).toEqual(finalNetworks);
         });
 
-        it('provides null for device_name when falsy', function() {
-          model.newInstanceSpec.source_type.type = 'image';
-          model.newInstanceSpec.vol_device_name = false;
-          model.newInstanceSpec.vol_create = true;
-
-          var finalSpec = model.createInstance();
-          expect(finalSpec.block_device_mapping_v2[0].device_name).toBeNull();
-        });
-
         it('should not have meta property if no metadata specified', function() {
           metadata = {};