Merge "Add "-no-warn-sample-unuse=true" to work around AutoFDO issue"

am: d810312751

Change-Id: I4889db3de3dc62d5261d19bc627c1aae1ec30318

cc/pgo.go

@@ -177,6 +177,10 @@ func (props *PgoProperties) addProfileUseFlags(ctx ModuleContext, flags Flags) F
 		// if profileFile gets updated
 		flags.CFlagsDeps = append(flags.CFlagsDeps, profileFilePath)
 		flags.LdFlagsDeps = append(flags.LdFlagsDeps, profileFilePath)
+
+		if props.isSampling() {
+			flags.Local.LdFlags = append(flags.Local.LdFlags, "-Wl,-mllvm,-no-warn-sample-unused=true")
+		}
 	}
 	return flags
 }