Remove problematic decoding unit test (#166)

Author: paulb777

GoogleDataTransport/GDTCORTests/Unit/GDTCORMetricsMetadataTest.m

@@ -108,36 +108,4 @@ - (void)testSecureCoding {
   XCTAssertEqualObjects(decodedMetricsMetadata, metricsMetadata);
 }
 
-- (void)testSecureCoding_WhenEncodingIsCorrupted {
-  // Given
-  // - Create an invalid instance and write its encoding to a file. When
-  //   decoding, the invalid encoding should be treated as a corrupt encoding.
-  GDTCORMetricsMetadata *corruptedMetadata =
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wincompatible-pointer-types"
-      [GDTCORMetricsMetadata metadataWithCollectionStartDate:@"date"
-                                            logSourceMetrics:[GDTCORLogSourceMetrics metrics]];
-#pragma clang diagnostic pop
-
-  NSError *encodeError;
-  NSData *encodedMetricsMetadata = GDTCOREncodeArchive(corruptedMetadata, nil, &encodeError);
-  XCTAssertNil(encodeError);
-  XCTAssertNotNil(encodedMetricsMetadata);
-
-  NSString *filePath = [NSTemporaryDirectory() stringByAppendingPathComponent:@"metadata.dat"];
-  NSError *writeError;
-  BOOL writeResult = GDTCORWriteDataToFile(encodedMetricsMetadata, filePath, &writeError);
-  XCTAssertNil(writeError);
-  XCTAssertTrue(writeResult);
-
-  // When
-  NSError *decodeError;
-  GDTCORMetricsMetadata *decodedMetricsMetadata =
-      (GDTCORMetricsMetadata *)GDTCORDecodeArchiveAtPath(GDTCORMetricsMetadata.class, filePath,
-                                                         &decodeError);
-  // Then
-  XCTAssertNotNil(decodeError);
-  XCTAssertNil(decodedMetricsMetadata);
-}
-
 @end