Add recovery image sdk trait to cc_library_headers

Allows an sdk to require that a cc_library_headers module provides a
recovery image variant for the prebuilt.

Previously, "recovery_available: true" would be set in the generated
prebuilt snapshot for any sdk member that specified
"recovery_available: true" in the source module. This change will only
add that setting to the snapshot if the recovery image variant trait
was explicitly requested for a member.

Bug: 195754365
Test: m nothing
Change-Id: I7d79ccdec843127f7852d82b4b163021e30a79a7
diff --git a/cc/Android.bp b/cc/Android.bp
index 190d55e..07aa7cb 100644
--- a/cc/Android.bp
+++ b/cc/Android.bp
@@ -60,6 +60,7 @@
         "binary.go",
         "binary_sdk_member.go",
         "fuzz.go",
+        "image_sdk_traits.go",
         "library.go",
         "library_headers.go",
         "library_sdk_member.go",
diff --git a/cc/image_sdk_traits.go b/cc/image_sdk_traits.go
new file mode 100644
index 0000000..371bb24
--- /dev/null
+++ b/cc/image_sdk_traits.go
@@ -0,0 +1,33 @@
+// Copyright 2021 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package cc
+
+import "android/soong/android"
+
+// This file contains support for the image variant sdk traits.
+
+func init() {
+	android.RegisterSdkMemberTrait(recoveryImageRequiredSdkTrait)
+}
+
+type imageSdkTraitStruct struct {
+	android.SdkMemberTraitBase
+}
+
+var recoveryImageRequiredSdkTrait android.SdkMemberTrait = &imageSdkTraitStruct{
+	SdkMemberTraitBase: android.SdkMemberTraitBase{
+		PropertyName: "recovery_image_required",
+	},
+}
diff --git a/cc/library_headers.go b/cc/library_headers.go
index f88b801..4022392 100644
--- a/cc/library_headers.go
+++ b/cc/library_headers.go
@@ -35,6 +35,7 @@
 		HostOsDependent: true,
 		Traits: []android.SdkMemberTrait{
 			nativeBridgeSdkTrait,
+			recoveryImageRequiredSdkTrait,
 		},
 	},
 	prebuiltModuleType: "cc_prebuilt_library_headers",
diff --git a/cc/library_sdk_member.go b/cc/library_sdk_member.go
index 73187bd..a28ccd0 100644
--- a/cc/library_sdk_member.go
+++ b/cc/library_sdk_member.go
@@ -133,6 +133,16 @@
 				imageVariations: []blueprint.Variation{{Mutator: "image", Variation: android.CoreVariation}},
 				targets:         targets,
 			})
+
+			// If required add additional dependencies on the image:recovery variants.
+			if ctx.RequiresTrait(lib, recoveryImageRequiredSdkTrait) {
+				memberDependencies = append(memberDependencies, memberDependency{
+					imageVariations: []blueprint.Variation{{Mutator: "image", Variation: android.RecoveryVariation}},
+					// Only add a dependency on the first target as that is the only one which will have an
+					// image:recovery variant.
+					targets: targets[:1],
+				})
+			}
 		}
 
 		// For each dependency in the list add dependencies on the targets with the correct variations.
@@ -189,7 +199,7 @@
 		pbm.AddProperty("native_bridge_supported", true)
 	}
 
-	if proptools.Bool(ccModule.Properties.Recovery_available) {
+	if ctx.RequiresTrait(recoveryImageRequiredSdkTrait) {
 		pbm.AddProperty("recovery_available", true)
 	}