Fix cache key generation of CppModuleMapAction.

It was missing multiple members in its key computation.

RELNOTES: Fix .cppmap file re-generation.

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MOS_MIGRATED_REVID=86074231
diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppModuleMapAction.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppModuleMapAction.java
index a350fc4..a503f1f 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/CppModuleMapAction.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/CppModuleMapAction.java
@@ -149,8 +149,14 @@
     for (CppModuleMap dep : dependencies) {
       f.addPath(dep.getArtifact().getExecPath());
     }
+    f.addInt(additionalExportedHeaders.size());
+    for (PathFragment path : additionalExportedHeaders) {
+      f.addPath(path);
+    }
     f.addPath(cppModuleMap.getArtifact().getExecPath());
     f.addString(cppModuleMap.getName());
+    f.addBoolean(moduleMapHomeIsCwd);
+    f.addBoolean(compiledModule);
     return f.hexDigestAndReset();
   }