Analyzer improvements

- strengthen analyzer against error messages that point past the
  bottom of the file.

- ignore any errors in intl's auto-generated files.

packages/flutter_tools/lib/src/commands/analyze.dart

@@ -256,9 +256,9 @@ class AnalyzeCommand extends FlutterCommand {
     ];
 
     RegExp generalPattern = new RegExp(r'^\[(error|warning|hint|lint)\] (.+) \(([^(),]+), line ([0-9]+), col ([0-9]+)\)$');
-    RegExp ignorePattern = new RegExp(r'// analyzer says "([^"]+)"');
+    RegExp allowedIdentifiersPattern = new RegExp(r'_?([A-Z]|_+)\b');
     RegExp constructorTearOffsPattern = new RegExp('.+#.+// analyzer doesn\'t like constructor tear-offs');
-    RegExp allowedIdentifiers = new RegExp(r'_?([A-Z]|_+)\b');
+    RegExp ignorePattern = new RegExp(r'// analyzer says "([^"]+)"');
 
     List<String> errorLines = output.toString().split('\n');
     for (String errorLine in errorLines) {
@@ -272,12 +272,16 @@ class AnalyzeCommand extends FlutterCommand {
           int colNumber = int.parse(groups[5]);
           File source = new File(filename);
           List<String> sourceLines = source.readAsLinesSync();
-          String sourceLine = sourceLines[lineNumber-1];
+          String sourceLine = (lineNumber < sourceLines.length) ? sourceLines[lineNumber-1] : '';
           bool shouldIgnore = false;
           if (filename.endsWith('.mojom.dart')) {
+            // autogenerated code - TODO(ianh): Fix the Dart mojom compiler
+            shouldIgnore = true;
+          } else if ((sourceLines[0] == '/**') && (' * DO NOT EDIT. This is code generated'.matchAsPrefix(sourceLines[1]) != null)) {
+            // autogenerated code - TODO(ianh): Fix the intl package resource generator
             shouldIgnore = true;
           } else if (level == 'lint' && errorMessage == 'Name non-constant identifiers using lowerCamelCase.') {
-            if (allowedIdentifiers.matchAsPrefix(sourceLine, colNumber-1) != null)
+            if (allowedIdentifiersPattern.matchAsPrefix(sourceLine, colNumber-1) != null)
               shouldIgnore = true;
           } else if (constructorTearOffsPattern.allMatches(sourceLine).isNotEmpty) {
             shouldIgnore = true;