Remove FileParseExceptionHandler from FileSystemState.

This handler is holding a reference to AnalysisDriver, which references
AnalysisDriverScheduler, etc. And FileSystemState is referenced
from _ContentCacheWrapper that we set for AnlysisContext(s). So, I
suspect that this might cause a memory leak.

This mostly reverts https://dart-review.googlesource.com/c/sdk/+/17561

R=brianwilkerson@google.com

Change-Id: Ib8aebcbab4c37399fcfe35a604598356ad2df87b
Reviewed-on: https://dart-review.googlesource.com/c/79433
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

Author: scheglov

pkg/analyzer/lib/src/dart/analysis/driver.dart

@@ -1282,8 +1282,8 @@ class AnalysisDriver implements AnalysisDriverGeneric {
           libraryContext?.dispose();
         }
       } catch (exception, stackTrace) {
-        String contextKey = _storeExceptionContextDuringAnalysis(
-            path, library, exception, stackTrace);
+        String contextKey =
+            _storeExceptionContext(path, library, exception, stackTrace);
         throw new _ExceptionState(exception, stackTrace, contextKey);
       }
     });
@@ -1351,16 +1351,16 @@ class AnalysisDriver implements AnalysisDriverGeneric {
   void _createFileTracker() {
     _fillSalt();
     _fsState = new FileSystemState(
-        _logger,
-        _byteStore,
-        _contentOverlay,
-        _resourceProvider,
-        sourceFactory,
-        analysisOptions,
-        _unlinkedSalt,
-        _linkedSalt,
-        externalSummaries: _externalSummaries,
-        parseExceptionHandler: _storeExceptionContextDuringParsing);
+      _logger,
+      _byteStore,
+      _contentOverlay,
+      _resourceProvider,
+      sourceFactory,
+      analysisOptions,
+      _unlinkedSalt,
+      _linkedSalt,
+      externalSummaries: _externalSummaries,
+    );
     _fileTracker = new FileTracker(_logger, _fsState, _changeHook);
   }
 
@@ -1573,9 +1573,27 @@ class AnalysisDriver implements AnalysisDriverGeneric {
         .toBuffer();
   }
 
-  String _storeExceptionContext(AnalysisDriverExceptionContextBuilder builder) {
+  String _storeExceptionContext(
+      String path, FileState libraryFile, exception, StackTrace stackTrace) {
+    if (allowedNumberOfContextsToWrite <= 0) {
+      return null;
+    } else {
+      allowedNumberOfContextsToWrite--;
+    }
     try {
-      List<int> bytes = builder.toBuffer();
+      List<AnalysisDriverExceptionFileBuilder> contextFiles = libraryFile
+          .transitiveFiles
+          .map((file) => new AnalysisDriverExceptionFileBuilder(
+              path: file.path, content: file.content))
+          .toList();
+      contextFiles.sort((a, b) => a.path.compareTo(b.path));
+      AnalysisDriverExceptionContextBuilder contextBuilder =
+          new AnalysisDriverExceptionContextBuilder(
+              path: path,
+              exception: exception.toString(),
+              stackTrace: stackTrace.toString(),
+              files: contextFiles);
+      List<int> bytes = contextBuilder.toBuffer();
 
       String _twoDigits(int n) {
         if (n >= 10) return '$n';
@@ -1604,53 +1622,6 @@ class AnalysisDriver implements AnalysisDriverGeneric {
     }
   }
 
-  String _storeExceptionContextDuringAnalysis(
-      String path, FileState libraryFile, exception, StackTrace stackTrace) {
-    if (allowedNumberOfContextsToWrite <= 0) {
-      return null;
-    } else {
-      allowedNumberOfContextsToWrite--;
-    }
-    try {
-      List<AnalysisDriverExceptionFileBuilder> contextFiles = libraryFile
-          .transitiveFiles
-          .map((file) => new AnalysisDriverExceptionFileBuilder(
-              path: file.path, content: file.content))
-          .toList();
-      contextFiles.sort((a, b) => a.path.compareTo(b.path));
-      AnalysisDriverExceptionContextBuilder contextBuilder =
-          new AnalysisDriverExceptionContextBuilder(
-              path: path,
-              exception: exception.toString(),
-              stackTrace: stackTrace.toString(),
-              files: contextFiles);
-      return _storeExceptionContext(contextBuilder);
-    } catch (_) {
-      return null;
-    }
-  }
-
-  String _storeExceptionContextDuringParsing(
-      FileState file, exception, StackTrace stackTrace) {
-    if (allowedNumberOfContextsToWrite <= 0) {
-      return null;
-    } else {
-      allowedNumberOfContextsToWrite--;
-    }
-    try {
-      var fileBuilder = new AnalysisDriverExceptionFileBuilder(
-          path: file.path, content: file.content);
-      var contextBuilder = new AnalysisDriverExceptionContextBuilder(
-          path: file.path,
-          exception: exception.toString(),
-          stackTrace: stackTrace.toString(),
-          files: [fileBuilder]);
-      return _storeExceptionContext(contextBuilder);
-    } catch (_) {
-      return null;
-    }
-  }
-
   /**
    * If the driver is used in the read-only mode with infinite cache,
    * we should not allow invocations that change files.

pkg/analyzer/lib/src/dart/analysis/file_state.dart

@@ -10,7 +10,9 @@ import 'package:analyzer/dart/ast/standard_ast_factory.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/error/listener.dart';
 import 'package:analyzer/file_system/file_system.dart';
+import 'package:analyzer/src/dart/analysis/byte_store.dart';
 import 'package:analyzer/src/dart/analysis/defined_names.dart';
+import 'package:analyzer/src/dart/analysis/performance_logger.dart';
 import 'package:analyzer/src/dart/analysis/referenced_names.dart';
 import 'package:analyzer/src/dart/analysis/top_level_declaration.dart';
 import 'package:analyzer/src/dart/analysis/unlinked_api_signature.dart';
@@ -21,25 +23,17 @@ import 'package:analyzer/src/generated/parser.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/generated/utilities_dart.dart';
 import 'package:analyzer/src/source/source_resource.dart';
+import 'package:analyzer/src/summary/api_signature.dart';
 import 'package:analyzer/src/summary/format.dart';
 import 'package:analyzer/src/summary/idl.dart';
 import 'package:analyzer/src/summary/name_filter.dart';
 import 'package:analyzer/src/summary/package_bundle_reader.dart';
 import 'package:analyzer/src/summary/summarize_ast.dart';
 import 'package:convert/convert.dart';
 import 'package:crypto/crypto.dart';
-import 'package:analyzer/src/dart/analysis/byte_store.dart';
-import 'package:analyzer/src/summary/api_signature.dart';
-import 'package:analyzer/src/dart/analysis/performance_logger.dart';
 import 'package:front_end/src/fasta/scanner/token.dart';
 import 'package:meta/meta.dart';
 
-/**
- * The type of the function that is notified about an error during parsing.
- */
-typedef void FileParseExceptionHandler(
-    FileState file, exception, StackTrace stackTrace);
-
 /**
  * [FileContentOverlay] is used to temporary override content of files.
  */
@@ -377,10 +371,7 @@ class FileState {
       return PerformanceStatistics.parse.makeCurrentWhile(() {
         return _parse(errorListener);
       });
-    } catch (exception, stackTrace) {
-      if (_fsState.parseExceptionHandler != null) {
-        _fsState.parseExceptionHandler(this, exception, stackTrace);
-      }
+    } catch (_) {
       return _createEmptyCompilationUnit();
     }
   }
@@ -730,15 +721,6 @@ class FileSystemState {
    */
   final SummaryDataStore externalSummaries;
 
-  /**
-   * The optional handler for scanning and parsing exceptions.
-   *
-   * We hope that these exceptions never happen, but we might need to get
-   * additional information if there are exception when we are replacing
-   * Analyzer's scanner and parser with implementations from FrontEnd.
-   */
-  final FileParseExceptionHandler parseExceptionHandler;
-
   /**
    * Mapping from a URI to the corresponding [FileState].
    */
@@ -807,10 +789,11 @@ class FileSystemState {
     this._unlinkedSalt,
     this._linkedSalt, {
     this.externalSummaries,
-    this.parseExceptionHandler,
   }) {
-    _fileContentCache =
-        _FileContentCache.getInstance(_resourceProvider, _contentOverlay);
+    _fileContentCache = _FileContentCache.getInstance(
+      _resourceProvider,
+      _contentOverlay,
+    );
     _testView = new FileSystemStateTestView(this);
   }