Compile all fiddle examples locally

Motivation: it would be a good idea if the API documentation examples
were checked into the skia repository, so we could make sure they
compile as part of the commit queue.

Fiddle would make/update a named fiddle each time it gets a new
commit of Skia, extracted from the code in the examples/ directory.
The docs would point at those named fiddles.  Named fiddles have urls
in the form:

    https://fiddle.skia.org/c/@Bitmap_000

Then we would stick a link to the example into the header documentation
like this:

    /** Allocates the pixel memory for the bitmap, given its dimensions
        and SkColorType. Returns true on success, where success means
        either setPixels() or setPixelRef() was called.

        @param bitmap  SkBitmap containing SkImageInfo as input, and
                       SkPixelRef as output
        @return        true if SkPixelRef was allocated

        @example       https://fiddle.skia.org/c/@Bitmap_000
    */
    bool allocPixelRef(SkBitmap* bitmap) override;

There are still around 200 disabled examples that need to be fixed
(these result from API changes since the author left).

Change-Id: I14a31348a9ccaaa31f65424b91e3a3533d2583a7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/198824
Commit-Queue: Hal Canary <halcanary@google.com>
Reviewed-by: Leon Scroggins <scroggo@google.com>
Reviewed-by: Joe Gregorio <jcgregorio@google.com>
diff --git a/docs/examples/Image_041.cpp b/docs/examples/Image_041.cpp
new file mode 100644
index 0000000..4431c9d
--- /dev/null
+++ b/docs/examples/Image_041.cpp
@@ -0,0 +1,35 @@
+#if 0  // Disabled until updated to use current API.
+// Copyright 2019 Google LLC.
+// Use of this source code is governed by a BSD-style license that can be found in the LICENSE file.
+#include "fiddle/examples.h"
+// HASH=a8b8bd4bfe968e2c63085f867665227f
+REG_FIDDLE(Image_041, 256, 80, false, 0) {
+class TestImageGenerator : public SkImageGenerator {
+public:
+    TestImageGenerator() : SkImageGenerator(SkImageInfo::MakeN32Premul(10, 10)) {}
+    ~TestImageGenerator() override {}
+protected:
+    bool onGetPixels(const SkImageInfo& info, void* pixelPtr, size_t rowBytes,
+                     const Options& options) override {
+        SkPMColor* pixels = static_cast<SkPMColor*>(pixelPtr);
+        for (int y = 0; y < info.height(); ++y) {
+            for (int x = 0; x < info.width(); ++x) {
+                pixels[y * info.width() + x] = 0xff223344 + y * 0x000C0811;
+            }
+        }
+        return true;
+    }
+};
+
+void draw(SkCanvas* canvas) {
+    auto gen = std::unique_ptr<TestImageGenerator>(new TestImageGenerator());
+    sk_sp<SkImage> image(SkImage::MakeFromGenerator(std::move(gen)));
+    SkString lazy(image->isLazyGenerated() ? "is lazy" : "not lazy");
+    canvas->scale(8, 8);
+    canvas->drawImage(image, 0, 0, nullptr);
+    SkPaint paint;
+    paint.setTextSize(4);
+    canvas->drawString(lazy, 2, 5, paint);
+}
+}  // END FIDDLE
+#endif  // Disabled until updated to use current API.