Failed to detect generated javascript files in public/build

I am getting the below error when i do make run. Could someone help me fix it?

go build -ldflags -w -X main.version=6.4.0-pre -X main.commit=6d3a05a02 -X main.buildstamp=1566466956 -X main.buildBranch=master -o ./bin/grafana-cli ./pkg/cmd/grafana-cli
[Bra] 08-27 11:12:36 [DEBUG] Running: go [run build.go -dev build-server]
Version: 6.4.0-pre, Linux Version: 6.4.0, Package Iteration: 1566884559pre
go build -ldflags -w -X main.version=6.4.0-pre -X main.commit=6d3a05a02 -X main.buildstamp=1566466956 -X main.buildBranch=master -o ./bin/grafana-server ./pkg/cmd/grafana-server
[Bra] 08-27 11:12:47 [DEBUG] Running: ./bin/grafana-server [-packaging=dev cfg:app_mode=development]
EROR[08-27|11:12:48] Failed to detect generated javascript files in public/build logger=settings
INFO[08-27|11:12:48] Starting Grafana logger=server version=6.4.0-pre commit=6d3a05a02 branch=master compiled=2019-08-22T15:12:36+0530
INFO[08-27|11:12:48] Config loaded from logger=settings file=/home/ukankal/code/goProjects/src/github.com/grafana/grafana/conf/defaults.ini
INFO[08-27|11:12:48] Config loaded from logger=settings file=/home/ukankal/code/goProjects/src/github.com/grafana/grafana/conf/custom.ini
INFO[08-27|11:12:48] Config overridden from command line logger=settings arg=“app_mode=development”
INFO[08-27|11:12:48] Path Home logger=settings path=/home/ukankal/code/goProjects/src/github.com/grafana/grafana
INFO[08-27|11:12:48] Path Data logger=settings path=/var/lib/grafana
INFO[08-27|11:12:48] Path Logs logger=settings path=/var/log/grafana
INFO[08-27|11:12:48] Path Plugins logger=settings path=/var/lib/grafana/plugins
INFO[08-27|11:12:48] Path Provisioning logger=settings path=/home/ukankal/code/goProjects/src/github.com/grafana/grafana/conf/provisioning
INFO[08-27|11:12:48] App mode development logger=settings
INFO[08-27|11:12:48] Initializing SqlStore logger=server
INFO[08-27|11:12:48] Connecting to DB logger=sqlstore dbtype=postgres
INFO[08-27|11:12:48] Starting DB migration logger=migrator
INFO[08-27|11:12:54] Initializing HTTPServer logger=server
INFO[08-27|11:12:54] Initializing InternalMetricsService logger=server
INFO[08-27|11:12:54] Initializing RemoteCache logger=server
INFO[08-27|11:12:54] Initializing QuotaService logger=server
INFO[08-27|11:12:54] Initializing ServerLockService logger=server
INFO[08-27|11:12:54] Initializing UserAuthTokenService logger=server
INFO[08-27|11:12:54] Initializing PluginManager logger=server
INFO[08-27|11:12:54] Starting plugin search logger=plugins
INFO[08-27|11:12:55] Initializing RenderingService logger=server
INFO[08-27|11:12:55] Initializing AlertEngine logger=server
INFO[08-27|11:12:55] Initializing DatasourceCacheService logger=server
INFO[08-27|11:12:55] Initializing HooksService logger=server
INFO[08-27|11:12:55] Initializing LoginService logger=server
INFO[08-27|11:12:55] Initializing SearchService logger=server
INFO[08-27|11:12:55] Initializing TracingService logger=server
INFO[08-27|11:12:55] Initializing UsageStatsService logger=server
INFO[08-27|11:12:55] Initializing CleanUpService logger=server
INFO[08-27|11:12:55] Initializing NotificationService logger=server
INFO[08-27|11:12:55] Initializing provisioningServiceImpl logger=server
INFO[08-27|11:12:55] Backend rendering via phantomJS logger=rendering
INFO[08-27|11:12:55] Initializing Stream Manager
INFO[08-27|11:12:55] HTTP Server Listen logger=http.server address=0.0.0.0:3000 protocol=http subUrl= socket=

I got below error when i first did go get github.com/grafana/grafana,

package github.com/grafana/grafana: build constraints exclude all Go files in /home/ukankal/code/goProjects/src/github.com/grafana/grafana

then when i did make run, I got the below error.

EROR[08-27|11:12:48] Failed to detect generated javascript files in public/build logger=settings.

I am on ubuntu 18.04. I have been looking around for solution but I couldn’t see any issues logged about this error. I could really use someone’s help.

you can create dir in public.