Include images in dackka output

PiperOrigin-RevId: 416848472

javadoc_combined.gradle

@@ -67,12 +67,12 @@ class CombinedJavadocPlugin implements Plugin<Project> {
           }
         }
 
+        def dackkaOutputDir = project.file("$project.buildDir/docs/dackka")
         project.task(DACKKA_TASK_NAME, type: JavaExec) {
           doFirst {
             // Recreate the output directory to remove any leftover files from a previous run.
-            def outputDir = project.file("$project.buildDir/docs/dackka")
-            project.delete outputDir
-            project.mkdir outputDir
+            project.delete dackkaOutputDir
+            project.mkdir dackkaOutputDir
 
             // Download the Dackka JAR.
             new URL(DACKKA_JAR_URL).withInputStream {
@@ -104,7 +104,7 @@ class CombinedJavadocPlugin implements Plugin<Project> {
                 .filter({ f -> project.file(f).exists() }).join(";")
             def dependenciesString = project.files(dependencies).asPath.replace(':', ';')
             args("-moduleName", "",
-                "-outputDir", "$outputDir",
+                "-outputDir", "$dackkaOutputDir",
                 "-globalLinks", "$globalLinksString",
                 "-loggingLevel", "WARN",
                 "-sourceSet", "-src $sourcesString -classpath $dependenciesString",
@@ -113,6 +113,18 @@ class CombinedJavadocPlugin implements Plugin<Project> {
           }
           description = "Generates combined javadoc for developer.android.com."
           classpath = project.files(new File(getTemporaryDir(), "dackka.jar"))
+          doLast {
+            libraryModules.each { libraryModule ->
+              project.copy {
+                from "${libraryModule.projectDir}/src/main/javadoc"
+                into "${dackkaOutputDir}/reference/"
+              }
+              project.copy {
+                from "${libraryModule.projectDir}/src/main/javadoc"
+                into "${dackkaOutputDir}/reference/kotlin/"
+              }
+            }
+          }
         }
       }
     }