Reland "Don't key progams/pipelines on origin.""

Reland works around Adreno issue with this formulation of sk_Clockwise:
 (sk_RTFlip.y < 0.0 ? !gl_FrontFacing : gl_FrontFacing)

and instead adds this to the top of the function:
 bool sk_Clockwise = gl_FrontFacing;
 if (sk_RTFlip.y < 0.0) {
      sk_Clockwise = !sk_Clockwise;
 }

Original description:

SkSL language features that are origin sensitive now use a uniform
to conditionally flip their result rather than generating different
code.

Previously we would insert a "rt height" uniform if sk_FragCoord needed
to be flipped. sk_FragCoord,y was implemented as "realFragCoord.y" or
"rtHeight - realFragCoord.y" depending on SkSL::ProgramSettings::fFlipY.

Now we instead use a two component vector rtFlip and sk_FragCoord.y is
always "rtFlip.x + rtFlip.y*realFragCoord.y". We configure rtFlip as
either (0, 1) or (rtHeight, -1). sk_Clockwise and dFdy simiarly use
rtFlip.y to emit code that always works with either origin.

Bug: skia:12037
Change-Id: I3a2ad6f5667eb4dcd823b939abd5698f89b58929
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/425178
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
diff --git a/src/sksl/SkSLCompiler.cpp b/src/sksl/SkSLCompiler.cpp
index b8533cc..72d60d2 100644
--- a/src/sksl/SkSLCompiler.cpp
+++ b/src/sksl/SkSLCompiler.cpp
@@ -895,6 +895,10 @@
 bool Compiler::toSPIRV(Program& program, OutputStream& out) {
     TRACE_EVENT0("skia.shaders", "SkSL::Compiler::toSPIRV");
     AutoSource as(this, program.fSource.get());
+    ProgramSettings settings;
+    settings.fDSLUseMemoryPool = false;
+    dsl::Start(this, program.fConfig->fKind, settings);
+    dsl::DSLWriter::IRGenerator().fSymbolTable = program.fSymbols;
 #ifdef SK_ENABLE_SPIRV_VALIDATION
     StringStream buffer;
     SPIRVCodeGenerator cg(fContext.get(), &program, this, &buffer);
@@ -933,6 +937,7 @@
     SPIRVCodeGenerator cg(fContext.get(), &program, this, &out);
     bool result = cg.generateCode();
 #endif
+    dsl::End();
     return result;
 }