Make `isolated` always-off for Windows.

The library support isn't available on Windows, so it never makes sense to have `isolated: true` for Windows. This change makes code that builds for the host "just work" on Unix and at least build on Windows.

Change-Id: I352681cf64e18287336862e5694d4429e6b458ec
diff --git a/cc/test.go b/cc/test.go
index abf9162..32b1551 100644
--- a/cc/test.go
+++ b/cc/test.go
@@ -29,8 +29,8 @@
 	// if set, build against the gtest library. Defaults to true.
 	Gtest *bool
 
-	// if set, use the isolated gtest runner. Defaults to true if gtest is also true and the arch is Windows, false
-	// otherwise.
+	// if set, use the isolated gtest runner. Defaults to false.
+	// Isolation is not supported on Windows.
 	Isolated *bool
 }
 
@@ -198,8 +198,8 @@
 	return BoolDefault(test.LinkerProperties.Gtest, true)
 }
 
-func (test *testDecorator) isolated(ctx android.EarlyModuleContext) bool {
-	return BoolDefault(test.LinkerProperties.Isolated, false)
+func (test *testDecorator) isolated(ctx android.BaseModuleContext) bool {
+	return BoolDefault(test.LinkerProperties.Isolated, false) && !ctx.Windows()
 }
 
 // NOTE: Keep this in sync with cc/cc_test.bzl#gtest_copts