Add whitelist parameter to refEncodedData

include/core/SkEncodedFormat.h

+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkEncodedFormat_DEFINED
+#define SkEncodedFormat_DEFINED
+
+/**
+ *  Enum describing format of encoded data.
+ */
+enum SkEncodedFormat {
+    kUnknown_SkEncodedFormat,

[reed1, 2016/04/07 13:27:31]

why do we have an unknown value. From the API, its not clear why we need it

[scroggo_chromium, 2016/04/08 18:16:36]

This is unchanged. But FWIW, it mirrors how we have unknown SkColorTypes etc. We
could perhaps get away without it - I just did a git grep and only found one
instance. I could imagine using it for something for which we don't yet have an
enum here, but maybe in that case we should just add another enum.

[scroggo_chromium, 2016/04/12 14:41:19]

Removed until we discover we need it.

+    kBMP_SkEncodedFormat,
+    kGIF_SkEncodedFormat,
+    kICO_SkEncodedFormat,
+    kJPEG_SkEncodedFormat,
+    kPNG_SkEncodedFormat,
+    kWBMP_SkEncodedFormat,
+    kWEBP_SkEncodedFormat,
+    kPKM_SkEncodedFormat,   // ETC1
+    kKTX_SkEncodedFormat,
+    kASTC_SkEncodedFormat,
+    kDNG_SkEncodedFormat,
+};
+
+class SkEncodedFormatQuery {

[reed1, 2016/04/07 13:27:31]

may need a block comment summarizing why we have this class

[scroggo_chromium, 2016/04/08 18:16:36]

Acknowledged.

[scroggo_chromium, 2016/04/12 14:41:19]

I've moved this class into SkImageGenerator. I don't currently see other needs
for it, and it allows for a clearer block comment describing what it does.

+public:
+    virtual ~SkEncodedFormatQuery() {}
+
+    /**
+     *  Returns true if the specified format is supported.

[reed1, 2016/04/07 13:27:31]

... supported where/how?

[scroggo_chromium, 2016/04/08 18:16:36]

Acknowledged.

+     */
+    virtual bool supportedFormat(SkEncodedFormat) = 0;
+
+    /**
+     *  Given the beginning of an encoded image, returns true if that format is supported.
+     *
+     *  @param data points to the beginning of the encoded image.
+     *
+     *  @param length The number of bytes available to read. It need not be the entire image,
+     *                but if it is too small to make a format determination, the query may return
+     *                false where if given more data, it might have returned true.
+     */
+    virtual bool supportedFormatFromData(const void* data, size_t length) = 0;

[reed1, 2016/04/07 13:27:31]

Not sure what supported means here. "I can encode into the same format as this
data is encoded as"?

[scroggo_chromium, 2016/04/08 18:16:36]

Acknowledged.

[scroggo_chromium, 2016/04/12 14:41:19]

This version has been removed from the new class.

+};
+
+
+#endif  // SkEncodedFormat_DEFINED