Fix some doc lint warnings (#939)

Author: Ramon Nogueira

plugin/ochttp/span_annotating_client_trace.go

@@ -29,6 +29,8 @@ type spanAnnotator struct {
 
 // TODO: Remove NewSpanAnnotator at the next release.
 
+// NewSpanAnnotator returns a httptrace.ClientTrace which annotates
+// all emitted httptrace events on the provided Span.
 // Deprecated: Use NewSpanAnnotatingClientTrace instead
 func NewSpanAnnotator(r *http.Request, s *trace.Span) *httptrace.ClientTrace {
 	return NewSpanAnnotatingClientTrace(r, s)

plugin/ochttp/stats.go

@@ -32,6 +32,7 @@ var (
 	ClientLatency = stats.Float64("opencensus.io/http/client/latency", "End-to-end latency", stats.UnitMilliseconds)
 )
 
+// Client measures supported for use in custom views.
 var (
 	ClientSentBytes = stats.Int64(
 		"opencensus.io/http/client/sent_bytes",

trace/tracestate/tracestate.go

@@ -12,6 +12,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// Package tracestate implements support for the Tracestate header of the
+// W3C TraceContext propagation format.
 package tracestate
 
 import (