Revert "Switch to the new SkSL lexer."

This reverts commit c576e93d174f3106e072a2f506bca3990b541265.

Reason for revert: ASAN failures

Original change's description:
> Switch to the new SkSL lexer.
> 
> This completely replaces flex with a new in-house lexical analyzer generator,
> which we have done for performance and memory usage reasons. Flex requires us
> to copy strings every time we need the text of a token, whereas this new lexer
> allows us to handle strings as a (non-null-terminated) pointer and length
> everywhere, eliminating most string copies.
> 
> Bug: skia:
> Change-Id: I2add26efc9e20cb699520e82abcf713af3968aca
> Reviewed-on: https://skia-review.googlesource.com/39780
> Reviewed-by: Brian Salomon <bsalomon@google.com>
> Commit-Queue: Ethan Nicholas <ethannicholas@google.com>

TBR=bsalomon@google.com,ethannicholas@google.com

Change-Id: If27b750a5f696d06a6bcffed12fe9f0598e084a6
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: skia:
Reviewed-on: https://skia-review.googlesource.com/44881
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>

1 files changed, 1 insertions, 35 deletions

diff --git a/BUILD.gn b/BUILD.gn
index ef2ac0751f..1c328b0452 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -45,7 +45,6 @@ declare_args() {
   skia_vulkan_sdk = getenv("VULKAN_SDK")
   skia_qt_path = getenv("QT_PATH")
   skia_compile_processors = false
-  skia_lex = false
 
   skia_jumper_clang = ""
   skia_jumper_objdump = ""
@@ -412,7 +411,7 @@ optional("fontmgr_fuchsia") {
   ]
 }
 
-if (skia_lex) {
+if (skia_compile_processors) {
   executable("sksllex") {
     sources = [
       "src/sksl/lex/Main.cpp",
@@ -423,38 +422,6 @@ if (skia_lex) {
     include_dirs = [ "src/sksl/lex" ]
   }
 
-  action("run_sksllex") {
-    script = "gn/run_sksllex.py"
-    sources = [
-      "src/sksl/lex/layout.lex",
-      "src/sksl/lex/sksl.lex",
-    ]
-
-    # GN insists its outputs should go somewhere underneath target_out_dir, so we trick it with a
-    # path that starts with target_out_dir and then uses ".." to back up into the src dir.
-    outputs = [
-      "$target_out_dir/" +
-          rebase_path("src/sksl/lex/SkSLLexer.h", target_out_dir),
-      # the script also modifies the corresponding .cpp file, but if we tell GN that it gets
-      # confused due to the same file being named by two different paths
-    ]
-    sksllex_path = "$root_out_dir/"
-    sksllex_path += "sksllex"
-    if (host_os == "win") {
-      sksllex_path += ".exe"
-    }
-    args = [
-      rebase_path(sksllex_path),
-      rebase_path("bin/clang-format"),
-      rebase_path("src"),
-    ]
-  }
-} else {
-  group("run_sksllex") {
-  }
-}
-
-if (skia_compile_processors) {
   executable("skslc") {
     defines = [ "SKSL_STANDALONE" ]
     sources = [
@@ -515,7 +482,6 @@ optional("gpu") {
   enabled = skia_enable_gpu
   deps = [
     ":compile_processors",
-    ":run_sksllex",
   ]
   public_defines = []