Fix coverage sanitizer builds

Disable coverage for static binaries where address sanitizer is
disabled, and disable coverage in the mutator when disabling address
sanitizer.

Bug: 29188876
Change-Id: Ia1a21878c3f34cd295a6dec49608c412eb09e7b1
diff --git a/cc/sanitize.go b/cc/sanitize.go
index fb7cb37..b79e0c7 100644
--- a/cc/sanitize.go
+++ b/cc/sanitize.go
@@ -140,6 +140,7 @@
 
 	if ctx.staticBinary() {
 		s.Address = nil
+		s.Coverage = nil
 		s.Thread = nil
 	}
 
@@ -317,6 +318,9 @@
 	switch t {
 	case asan:
 		sanitize.Properties.Sanitize.Address = boolPtr(b)
+		if !b {
+			sanitize.Properties.Sanitize.Coverage = nil
+		}
 	case tsan:
 		sanitize.Properties.Sanitize.Thread = boolPtr(b)
 	default: