Introduce build configuration to summary building.

pkg/analyzer/lib/src/summary/summary_file_builder.dart

Index: pkg/analyzer/lib/src/summary/summary_file_builder.dart
diff --git a/pkg/analyzer/lib/src/summary/summary_file_builder.dart b/pkg/analyzer/lib/src/summary/summary_file_builder.dart
index d4097706616456c7d461889b11b6ba088fb9b15f..c4b9e6b1ae124bf402e63f000f100444dc988e68 100644
--- a/pkg/analyzer/lib/src/summary/summary_file_builder.dart
+++ b/pkg/analyzer/lib/src/summary/summary_file_builder.dart
@@ -46,13 +46,70 @@ class BuilderOutput {
   }
 }
 
+/**
+ * Summary build configuration.
+ */
+class SummaryBuildConfig {
+
+  /**
+   * Whether to use exclude informative data from created summaries.
+   */
+  final bool buildSummaryExcludeInformative;
+
+  /**
+   * Whether to output a summary in "fallback mode".
+   */
+  final bool buildSummaryFallback;
+  /**

[Paul Berry, 2016/06/17 19:57:51]

Nit: add a blank line here.

[pquitslund, 2016/06/17 20:47:32]

Done.

+   * Whether to create summaries using only ASTs, i.e. don't perform resolution.

[Paul Berry, 2016/06/17 19:57:51]

Technically, creating summaries from ASTs performs resolution; it just does it
in a different way that doesn't require creating a full element model.  Consider
changing to something like: "Whether to create summaries directly from ASTs,
i.e. don't create a full element model."

[pquitslund, 2016/06/17 20:47:32]

Done.

+   */
+  final bool buildSummaryOnlyAst;
+
+  /**
+   * Path to the dart SDK summary file.
+   */
+  final String dartSdkSummaryPath;
+
+  /**
+   * Whether to use strong static checking.
+   */
+  final bool strongMode;
+
+  /**
+   * List of summary input file paths.
+   */
+  final Iterable<String> summaryInputs;
+
+  /**
+   * Create a build configuration with the given set options.
+   */
+  SummaryBuildConfig(
+      {this.strongMode: false,
+      this.summaryInputs,
+      this.dartSdkSummaryPath,
+      this.buildSummaryExcludeInformative: false,
+      this.buildSummaryFallback: false,
+      this.buildSummaryOnlyAst: false});
+}
+
 class SummaryBuilder {
-  final AnalysisContext _context;
-  final Iterable<Source> _librarySources;
+  final AnalysisContext context;
+  final Iterable<Source> librarySources;
+  final SummaryBuildConfig config;
 
-  SummaryBuilder(this._librarySources, this._context);
+  /**
+   * Create a summary builder for these [librarySources] and [context] using the
+   * given [config].
+   */
+  SummaryBuilder(this.librarySources, this.context, this.config);
+
+  /**
+   * Create an SDK summary builder for the dart SDK at the given [sdkPath],
+   * using this [config].
+   */
+  factory SummaryBuilder.forSdk(String sdkPath, SummaryBuildConfig config) {
+    bool strongMode = config.strongMode;
 
-  factory SummaryBuilder.forSdk(String sdkPath, bool strongMode) {
     //
     // Prepare SDK.
     //
@@ -76,10 +133,10 @@ class SummaryBuilder {
       librarySources.add(sdk.mapDartUri(uri));
     }
 
-    return new SummaryBuilder(librarySources, sdk.context);
+    return new SummaryBuilder(librarySources, sdk.context, config);
   }
 
-  BuilderOutput build() => new _Builder(_context, _librarySources).build();
+  BuilderOutput build() => new _Builder(context, librarySources).build();
 }
 
 /**
@@ -123,7 +180,7 @@ class _Builder {
   _Builder(this.context, this.librarySources);
 
   /**
-   * Build a strong or spec mode summary for the Dart SDK at [sdkPath].
+   * Build summary output.
    */
   BuilderOutput build() {
     //