Support host platform cc builds

This involves handling of linux-* platforms (identifying them
appropriately as host), disabling unsupported Windows platform, and
denylisting of still-problematic modules.

Test: mixed_droid, with verification that shared library artifacts
originate from bazel-out

Change-Id: Ib52db49a2d2a3c1ff9b76af23fd4f22cfc9182d0

android/bazel.go

@@ -188,6 +188,7 @@ var (
 		"packages/apps/QuickSearchBox":/* recursive = */ true,
 		"packages/apps/WallpaperPicker":/* recursive = */ false,
 
+		"prebuilts/gcc":/* recursive = */ true,
 		"prebuilts/sdk":/* recursive = */ false,
 		"prebuilts/sdk/current/extras/app-toolkit":/* recursive = */ false,
 		"prebuilts/sdk/current/support":/* recursive = */ false,
@@ -250,6 +251,8 @@ var (
 
 	// Per-module denylist to always opt modules out of both bp2build and mixed builds.
 	bp2buildModuleDoNotConvertList = []string{
+		"libprotobuf-cpp-full", "libprotobuf-cpp-lite", // Unsupported product&vendor suffix. b/204811222 and b/204810610.
+
 		"libc_malloc_debug", // depends on libunwindstack, which depends on unsupported module art_cc_library_statics
 
 		"libbase_ndk", // http://b/186826477, fails to link libctscamera2_jni for device (required for CtsCameraTestCases)
@@ -381,7 +384,11 @@ func ShouldKeepExistingBuildFileForDir(dir string) bool {
 
 // MixedBuildsEnabled checks that a module is ready to be replaced by a
 // converted or handcrafted Bazel target.
-func (b *BazelModuleBase) MixedBuildsEnabled(ctx BazelConversionPathContext) bool {
+func (b *BazelModuleBase) MixedBuildsEnabled(ctx ModuleContext) bool {
+	if ctx.Os() == Windows {
+		// Windows toolchains are not currently supported.
+		return false
+	}
 	if !ctx.Config().BazelContext.BazelEnabled() {
 		return false
 	}