[pgo] Allow profile gather and use flags to coexist for sampling PGO

Bug: 79161490
Test: presubmit
Change-Id: I90df9c04dbe2a423c06e9a966fe9bcaed0a84a65
diff --git a/cc/pgo.go b/cc/pgo.go
index 42bc5d2..674e1bb 100644
--- a/cc/pgo.go
+++ b/cc/pgo.go
@@ -290,15 +290,17 @@
 
 	// Add flags to profile this module based on its profile_kind
 	if props.ShouldProfileModule && props.isInstrumentation() {
-		return props.addInstrumentationProfileGatherFlags(ctx, flags)
+		props.addInstrumentationProfileGatherFlags(ctx, flags)
+		// Instrumentation PGO use and gather flags cannot coexist.
+		return flags
 	} else if props.ShouldProfileModule && props.isSampling() {
-		return props.addSamplingProfileGatherFlags(ctx, flags)
+		props.addSamplingProfileGatherFlags(ctx, flags)
 	} else if ctx.DeviceConfig().SamplingPGO() {
-		return props.addSamplingProfileGatherFlags(ctx, flags)
+		props.addSamplingProfileGatherFlags(ctx, flags)
 	}
 
 	if !ctx.Config().IsEnvTrue("ANDROID_PGO_NO_PROFILE_USE") {
-		return props.addProfileUseFlags(ctx, flags)
+		props.addProfileUseFlags(ctx, flags)
 	}
 
 	return flags