Update getHost methods to also copy host flags, for use in exec->host…

… transitions.

Part of work on execution transitions, bazelbuild#7935.

PiperOrigin-RevId: 248345771

src/main/java/com/google/devtools/build/lib/rules/cpp/CppOptions.java

@@ -918,6 +918,16 @@ public FragmentOptions getHost() {
     host.dontEnableHostNonhost = dontEnableHostNonhost;
     host.requireCtxInConfigureFeatures = requireCtxInConfigureFeatures;
     host.useStandaloneLtoIndexingCommandLines = useStandaloneLtoIndexingCommandLines;
+
+    // Save host options for further use.
+    host.hostCoptList = hostCoptList;
+    host.hostConlyoptList = hostConlyoptList;
+    host.hostCppCompiler = hostCppCompiler;
+    host.hostCrosstoolTop = hostCrosstoolTop;
+    host.hostCxxoptList = hostCxxoptList;
+    host.hostLibcTopLabel = hostLibcTopLabel;
+    host.hostLinkoptList = hostLinkoptList;
+
     return host;
   }