Fix bug, always keep fIsScaleTranslate in correct state

tests/QuickRejectTest.cpp

Index: tests/QuickRejectTest.cpp
diff --git a/tests/QuickRejectTest.cpp b/tests/QuickRejectTest.cpp
index b39484bd89c488578fa24b6a1db1d370a4bbfad8..1aee34632097febd08b38c291deaa1f076c049d4 100644
--- a/tests/QuickRejectTest.cpp
+++ b/tests/QuickRejectTest.cpp
@@ -7,6 +7,7 @@
 
 #include "SkCanvas.h"
 #include "SkDrawLooper.h"
+#include "SkLightingImageFilter.h"
 #include "SkTypes.h"
 #include "Test.h"
 
@@ -145,3 +146,26 @@ DEF_TEST(QuickReject, reporter) {
     test_layers(reporter);
     test_quick_reject(reporter);
 }
+
+// Regression test to make sure that we keep fIsScaleTranslate up to date on the canvas.

[tomhudson, 2016/08/19 15:09:03]

Presumably the point is that sometimes we set a matrix without going through
setMatrix(), and this tests that path? (one of those paths?)

[msarett, 2016/08/19 15:15:31]

Yes, updating comment.

+DEF_TEST(QuickReject_MatrixState, reporter) {
+    SkCanvas canvas(100, 100);
+
+    // Set rotation matrix.

[tomhudson, 2016/08/19 15:09:03]

Nit: this is not a useful comment?

[msarett, 2016/08/19 15:15:31]

Removed.

+    SkMatrix matrix;
+    matrix.setRotate(45.0f);
+    canvas.setMatrix(matrix);
+
+    // Set image filter.

[tomhudson, 2016/08/19 15:09:03]

Nit: nor is this.

[msarett, 2016/08/19 15:15:31]

Removed.

+    SkPaint paint;
+    sk_sp<SkImageFilter> filter = SkLightingImageFilter::MakeDistantLitDiffuse(
+            SkPoint3::Make(1.0f, 1.0f, 1.0f), 0xFF0000FF, 2.0f, 0.5f, nullptr);
+    REPORTER_ASSERT(reporter, filter);
+    paint.setImageFilter(filter);
+    SkCanvas::SaveLayerRec rec;
+    rec.fPaint = &paint;
+    canvas.saveLayer(rec);
+
+    // Call quickReject().  It will assert if the matrix is out of sync.

[tomhudson, 2016/08/19 15:09:03]

// quickReject() will assert if the matrix is out of sync.

[msarett, 2016/08/19 15:15:31]

Done.

+    canvas.quickReject(SkRect::MakeWH(100.0f, 100.0f));
+}