mixed builds: add cc_test bazel handler, and add adbd_test to staging allowlist.

This will allow the test_suites_{arm64, x86_64} CI targets on
git_master-bazel to build adbd_test with bazel in `m`.

This is currently implemented similar to the cc_binary handler to
hydrate the output path field.

The tradefed config is still currently handled by Soong in
testBinary#install, which is called from both ProcessBazelQueryResponse
and GenerateAndroidBuildActions. We'll move the tradefed config path to
a mixed builds handler when it's ready on the cc_test bazel rule side.

Tested with `atest` with cuttlefish. Since `atest` doesn't have a way to pass
--bazel-mode-staging to its internal call to Soong, so I manually tested
this by adding adbt_test to the prod allowlist, and confirmed that the
installed adbd_test is the same binary as the one in bazel-out.

Test: $ showcommands adbd_test | grep bazel-out | tail -n1

```
/bin/bash -c "rm -f
out/target/product/vsoc_x86_64/data/nativetest64/adbd_test/adbd_test &&
cp -f -d
out/bazel/output/execroot/__main__/bazel-out/android_x86_64_silvermont-opt-ST-59d4124ca041/bin/packages/modules/adb/adbd_test
out/target/product/vsoc_x86_64/data/nativetest64/adbd_test/adbd_test"
```

Test: Add adbd_test to prod allowlist and run 'lunch aosp_cf_x86_64_phone-userdebug; atest adbd_test', all tests pass.
Bug: 258426425
Bug: 261692372
Change-Id: I6be329f39d607af8daa1dc772b23e8dd0247418c

cc/cc.go

@@ -1858,7 +1858,22 @@ func (c *Module) QueueBazelCall(ctx android.BaseModuleContext) {
 	c.bazelHandler.QueueBazelCall(ctx, c.getBazelModuleLabel(ctx))
 }
 
+var (
+	mixedBuildSupportedCcTest = []string{
+		"adbd_test",
+	}
+)
+
+// IsMixedBuildSupported returns true if the module should be analyzed by Bazel
+// in any of the --bazel-mode(s). This filters at the module level and takes
+// precedence over the allowlists in allowlists/allowlists.go.
 func (c *Module) IsMixedBuildSupported(ctx android.BaseModuleContext) bool {
+	if c.testBinary() && !android.InList(c.Name(), mixedBuildSupportedCcTest) {
+		// Per-module rollout of mixed-builds for cc_test modules.
+		return false
+	}
+
+	// Enable mixed builds as long as the cc_* module type has a bazel handler.
 	return c.bazelHandler != nil
 }
 
@@ -1888,6 +1903,8 @@ func (c *Module) ProcessBazelQueryResponse(ctx android.ModuleContext) {
 	}
 	mctx.ctx = mctx
 
+	// TODO(b/244432500): Get the tradefed config from the bazel target instead
+	// of generating it with Soong.
 	c.maybeInstall(mctx, apexInfo)
 }
 
@@ -2038,6 +2055,9 @@ func (c *Module) maybeUnhideFromMake() {
 	}
 }
 
+// maybeInstall is called at the end of both GenerateAndroidBuildActions and
+// ProcessBazelQueryResponse to run the install hooks for installable modules,
+// like binaries and tests.
 func (c *Module) maybeInstall(ctx ModuleContext, apexInfo android.ApexInfo) {
 	if !proptools.BoolDefault(c.Installable(), true) {
 		// If the module has been specifically configure to not be installed then