[Omit needless words] Always dump both argument label and parameter name.

The default first argument label rules are confusing reviewers looking
at API dumps. Even though it's more verbose, always put in argument
labels explicitly.

Author: DougGregor

tools/swift-ide-test/swift-ide-test.cpp

@@ -258,6 +258,11 @@ SkipParameterNames("skip-parameter-names",
                    llvm::cl::desc("Whether to skip parameter names"),
                    llvm::cl::init(false));
 
+static llvm::cl::opt<bool>
+AlwaysArgumentLabels("always-argument-labels",
+  llvm::cl::desc("Whether to always print separate argument labels"),
+  llvm::cl::init(false));
+
 static llvm::cl::opt<bool>
 DisableAccessControl("disable-access-control",
     llvm::cl::desc("Disables access control, like a debugger"));
@@ -2571,6 +2576,9 @@ int main(int argc, char *argv[]) {
     if (options::SkipParameterNames) {
       PrintOpts.ArgAndParamPrinting
         = PrintOptions::ArgAndParamPrintingMode::ArgumentOnly;
+    } else if (options::AlwaysArgumentLabels) {
+      PrintOpts.ArgAndParamPrinting
+        = PrintOptions::ArgAndParamPrintingMode::BothAlways;
     }
   }
   if (options::SkipUnderscoredStdlibProtocols)

utils/swift-api-dump.py

@@ -229,7 +229,7 @@ def main():
     parser = create_parser()
     args = parser.parse_args()
 
-    cmd_common = [args.swift_ide_test, '-print-module', '-source-filename', source_filename, '-module-print-skip-overlay', '-skip-unavailable', '-skip-print-doc-comments']
+    cmd_common = [args.swift_ide_test, '-print-module', '-source-filename', source_filename, '-module-print-skip-overlay', '-skip-unavailable', '-skip-print-doc-comments', '-always-argument-labels']
 
     # Add -F / -I arguments.
     if args.framework_dir: