Remove SK_SUPPORT_LEGACY_DEEPFLATTENING.

This was needed for pictures before v33, and we're now requiring v35+.

Will follow up with the same for skia/ext/pixel_ref_utils_unittest.cc

BUG=skia:

Committed: https://skia.googlesource.com/skia/+/52c293547b973f7fb5de3c83f5062b07d759ab88

Review URL: https://codereview.chromium.org/769953002
diff --git a/tests/ImageFilterTest.cpp b/tests/ImageFilterTest.cpp
index 6fefe49..9fd4351 100644
--- a/tests/ImageFilterTest.cpp
+++ b/tests/ImageFilterTest.cpp
@@ -58,13 +58,6 @@
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(MatrixTestImageFilter)
 
 protected:
-#ifdef SK_SUPPORT_LEGACY_DEEPFLATTENING
-    explicit MatrixTestImageFilter(SkReadBuffer& buffer) : SkImageFilter(0, NULL) {
-        fReporter = static_cast<skiatest::Reporter*>(buffer.readFunctionPtr());
-        buffer.readMatrix(&fExpectedMatrix);
-    }
-#endif
-
     virtual void flatten(SkWriteBuffer& buffer) const SK_OVERRIDE {
         this->INHERITED::flatten(buffer);
         buffer.writeFunctionPtr(fReporter);
@@ -74,7 +67,7 @@
 private:
     skiatest::Reporter* fReporter;
     SkMatrix fExpectedMatrix;
-    
+
     typedef SkImageFilter INHERITED;
 };
 
@@ -487,7 +480,7 @@
     }
 }
 
-static void draw_saveLayer_picture(int width, int height, int tileSize, 
+static void draw_saveLayer_picture(int width, int height, int tileSize,
                                    SkBBHFactory* factory, SkBitmap* result) {
 
     SkMatrix matrix;
@@ -501,8 +494,8 @@
     paint.setImageFilter(imageFilter.get());
     SkPictureRecorder recorder;
     SkRect bounds = SkRect::Make(SkIRect::MakeXYWH(0, 0, 50, 50));
-    SkCanvas* recordingCanvas = recorder.beginRecording(SkIntToScalar(width), 
-                                                        SkIntToScalar(height), 
+    SkCanvas* recordingCanvas = recorder.beginRecording(SkIntToScalar(width),
+                                                        SkIntToScalar(height),
                                                         factory, 0);
     recordingCanvas->translate(-55, 0);
     recordingCanvas->saveLayer(&bounds, &paint);
@@ -625,11 +618,11 @@
 
     SkPictureRecorder recorder1, recorder2;
     // The only difference between these two pictures is that one has RTree aceleration.
-    SkCanvas* recordingCanvas1 = recorder1.beginRecording(SkIntToScalar(width), 
-                                                          SkIntToScalar(height), 
+    SkCanvas* recordingCanvas1 = recorder1.beginRecording(SkIntToScalar(width),
+                                                          SkIntToScalar(height),
                                                           NULL, 0);
-    SkCanvas* recordingCanvas2 = recorder2.beginRecording(SkIntToScalar(width), 
-                                                          SkIntToScalar(height), 
+    SkCanvas* recordingCanvas2 = recorder2.beginRecording(SkIntToScalar(width),
+                                                          SkIntToScalar(height),
                                                           &factory, 0);
     draw_blurred_rect(recordingCanvas1);
     draw_blurred_rect(recordingCanvas2);