Revert "Roll Skia to f802e75 (flutter#4670)" (flutter#4672)

This didn't break anything that we know of, but the engine is not
currently rollable to the framework due to a Dart bug. I'm reverting
this so we can get a fix landed for the Dart SDK, then roll, then
re-land this, then roll, to allow us to measure the performance impact
of the Dart SDK roll and the Skia roll independently.

This reverts commit 94ce14f.

DEPS

@@ -23,7 +23,7 @@ vars = {
   'fuchsia_git': 'https://fuchsia.googlesource.com',
   'github_git': 'https://github.com',
   'skia_git': 'https://skia.googlesource.com',
-  'skia_revision': 'f802e757646f424b563fdc1f5b5ee3c677659e98',
+  'skia_revision': '48661b868fbbf7a6193ef49bb6a05a0df61e7c45',
 
   # When updating the Dart revision, ensure that all entries that are
   # dependencies of Dart are also updated to match the entries in the

tools/licenses/pubspec.lock

@@ -2,60 +2,52 @@
 # See http://pub.dartlang.org/doc/glossary.html#lockfile
 packages:
   archive:
-    dependency: "direct main"
     description:
       name: archive
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.0.33"
   args:
-    dependency: "direct main"
     description:
       name: args
       url: "https://pub.dartlang.org"
     source: hosted
     version: "0.13.7"
   charcode:
-    dependency: transitive
     description:
       name: charcode
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.1"
   collection:
-    dependency: transitive
     description:
       name: collection
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.14.5"
   convert:
-    dependency: transitive
     description:
       name: convert
       url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.1"
   crypto:
-    dependency: "direct main"
     description:
       name: crypto
       url: "https://pub.dartlang.org"
     source: hosted
     version: "2.0.2+1"
   path:
-    dependency: "direct main"
     description:
       name: path
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.5.1"
   typed_data:
-    dependency: transitive
     description:
       name: typed_data
       url: "https://pub.dartlang.org"
     source: hosted
     version: "1.1.5"
 sdks:
-  dart: ">=1.21.0 <=2.0.0-dev.22.0"
+  dart: ">=1.21.0 <2.0.0"