Revert "sksl fragment processor support"

This reverts commit ccf59917d3fe7aaf59de714acfbd0596503f324f.

Reason for revert: breaking iOS bots

Original change's description:
> sksl fragment processor support
> 
> Bug: skia:
> Change-Id: Ia3b0305c2b0c78074303831f628fb01852b90d34
> Reviewed-on: https://skia-review.googlesource.com/17843
> Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
> Reviewed-by: Ben Wagner <benjaminwagner@google.com>
> Reviewed-by: Mike Klein <mtklein@google.com>

TBR=mtklein@google.com,benjaminwagner@google.com,ethannicholas@google.com

Change-Id: I0a33060c7c42c7b44c5c13d443ac42958291c2f1
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/20962
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>

1 files changed, 0 insertions, 56 deletions

diff --git a/src/sksl/README b/src/sksl/README
index 0c1712dc08..a16dd80858 100644
--- a/src/sksl/README
+++ b/src/sksl/README
@@ -9,7 +9,6 @@ in GLSL "in the wild", but it does bring a few of its own changes to the table.
 Skia uses the SkSL compiler to convert SkSL code to GLSL, GLSL ES, or SPIR-V
 before handing it over to the graphics driver.
 
-
 Differences from GLSL
 =====================
 
@@ -57,58 +56,3 @@ following differences between SkSL and GLSL:
 
 SkSL is still under development, and is expected to diverge further from GLSL
 over time.
-
-
-SkSL Fragment Processors
-========================
-
-An extension of SkSL allows for the creation of fragment processors in pure
-SkSL. The program defines its inputs similarly to a normal SkSL program (with
-'in' and 'uniform' variables), but the 'main()' function represents only this
-fragment processor's portion of the overall fragment shader.
-
-Within an '.fp' fragment processor file:
-
-* C++ code can be embedded in sections of the form:
-
-  @section_name { <arbitrary C++ code> }
-
-  Supported section are:
-    @header            (in the .h file, outside the class declaration)
-    @class             (in the .h file, inside the class declaration)
-    @cpp               (in the .cpp file)
-    @constructorParams (extra parameters to the constructor, comma-separated)
-    @constructor       (replaces the default constructor)
-    @initializers      (constructor initializer list, comma-separated)
-    @emitCode          (extra code for the emitCode function)
-    @fields            (extra private fields, each terminated with a semicolon)
-    @make              (replaces the default Make function)
-    @setData(<pdman>)  (extra code for the setData function, where <pdman> is
-                        the name of the GrGLSLProgramDataManager)
-    @test(<testData>)  (the body of the TestCreate function, where <testData> is
-                        the name of the GrProcessorTestData* parameter)
-* global 'in' variables represent data passed to the fragment processor at
-  construction time. These variables become constructor parameters and are
-  stored in fragment processor fields. vec2s map to SkPoints, and vec4s map to
-  SkRects (in x, y, width, height) order.
-* 'uniform' variables become, as one would expect, top-level uniforms. By
-  default they do not have any data provided to them; you will need to provide
-  them with data via the @setData section.
-* 'in uniform' variables are uniforms that are automatically wired up to
-  fragment processor constructor parameters
-* the 'sk_TransformedCoords2D' array provides access to 2D transformed
-  coordinates. sk_TransformedCoords2D[0] is equivalent to calling
-  fragBuilder->ensureCoords2D(args.fTransformedCoords[0]) (and the result is
-  cached, so you need not worry about using the value repeatedly).
-* 'colorSpaceXform' is a supported type. It is reflected within SkSL as a mat4,
-  and on the C++ side as sk_sp<GrColorSpaceXform>.
-* the texture() function can be passed a colorSpaceXform as an additional
-  parameter
-* Uniform variables support an additional 'when' layout key.
-  'layout(when=foo) uniform int x;' means that this uniform will only be
-  emitted when the 'foo' expression is true.
-* 'in' variables support an additional 'key' layout key.
-  'layout(key) uniform int x;' means that this uniform should be included in
-  the program's key. Matrix variables additionally support 'key=identity',
-  which causes the key to consider only whether or not the matrix is an
-  identity matrix.