Add support for forwarding symbol graph

rules/framework.bzl

@@ -522,12 +522,22 @@ def _copy_swiftmodule(ctx, framework_files):
     # only add a swift module to the SwiftInfo if we've actually got a swiftmodule
     swiftmodule_name = paths.split_extension(inputs.swiftmodule.basename)[0]
 
+    # find the first swift symbol_graph in the direct_modules of the deps of this target and forward it.
+    symbol_graph = None
+    for dep in ctx.attr.deps:
+        if SwiftInfo in dep:
+            module = dep[SwiftInfo].direct_modules[0]
+            if module.swift and module.swift.symbol_graph:
+                symbol_graph = module.swift.symbol_graph
+                break
+
     # need to include the swiftmodule here, even though it will be found through the framework search path,
     # since swift_library needs to know that the swiftdoc is an input to the compile action
     swift_module = swift_common.create_swift_module(
         swiftdoc = outputs.swiftdoc,
         swiftmodule = outputs.swiftmodule,
         swiftinterface = outputs.swiftinterface,
+        symbol_graph = symbol_graph,
     )
 
     if swiftmodule_name != ctx.attr.framework_name:
@@ -538,6 +548,7 @@ def _copy_swiftmodule(ctx, framework_files):
             swiftdoc = inputs.swiftdoc,
             swiftmodule = inputs.swiftmodule,
             swiftinterface = inputs.swiftinterface,
+            symbol_graph = symbol_graph,
         )
 
     return [