Revert "c2a: add option to use Cargo.toml.orig"

This reverts commit 2adbd7ed89d6f4cd7a4766a2a534697f498171a0.

Reason for revert: This doesn't work in all cases. For now I'll
instead use local patches for Cargo.toml :(

Change-Id: I0621796e694e2654a01fe9a38a307fd0a4ab8b15
diff --git a/scripts/cargo2android.py b/scripts/cargo2android.py
index 90b85bd..c571dab 100755
--- a/scripts/cargo2android.py
+++ b/scripts/cargo2android.py
@@ -1320,69 +1320,20 @@
         else:
           in_pkg = pkg_section.match(line) is not None
 
-  # Simple class for manipulation and error handling on Cargo.toml files.
-  class CargoToml(object):
-    cargo_toml = './Cargo.toml'
-    cargo_toml_orig = './Cargo.toml.orig'
-    cargo_toml_lines = None
-
-    def __init__(self, args):
-      if not os.access(self.cargo_toml, os.R_OK):
-        print('error: cannot find or read', self.cargo_toml)
-        return None
-
-      if args.orig_cargo_toml:
-        if not os.access(self.cargo_toml_orig, os.R_OK):
-          print('error: cannot find or read', self.cargo_toml_orig)
-          return None
-
-      # These arguments result in modifying the Cargo.toml.
-      # Save the original to be restored.
-      if args.orig_cargo_toml or args.add_workspace:
-        with open(self.cargo_toml, 'r') as in_file:
-          self.cargo_toml_lines = in_file.readlines()
-
-      # Temporarily replace Cargo.toml with Cargo.toml.orig.
-      # This is useful because crates.io removes dev-dependencies from Cargo.toml when
-      # version numbers are not specified, which is not possible for many crates due to
-      # https://github.com/rust-lang/cargo/issues/4242.
-      if args.orig_cargo_toml:
-        with open(self.cargo_toml, 'w') as out_file:
-          with open(self.cargo_toml_orig, 'r') as in_file:
-            lines = in_file.readlines()
-            out_file.writelines(lines)
-        if args.verbose:
-          print('### INFO: Overwrote Cargo.toml with Cargo.toml.orig')
-
-      # Add [workspace] to Cargo.toml if it is not there.
-      if args.add_workspace:
-        with open(self.cargo_toml, 'r') as in_file:
-          lines = in_file.readlines()
-        if '[workspace]\n' in lines:
-          print('### WARNING: found [workspace] in Cargo.toml')
-        else:
-          with open(self.cargo_toml, 'a') as out_file:
-            out_file.write('[workspace]\n')
-            if args.verbose:
-              print('### INFO: added [workspace] to Cargo.toml')
-
-    def restore(self, args):
-      if self.cargo_toml_lines is not None:
-        with open(self.cargo_toml, 'w') as out_file:
-          out_file.writelines(self.cargo_toml_lines)
-        if args.verbose:
-          print('### INFO: restored original Cargo.toml')
-
   def run_cargo(self):
     """Calls cargo -v and save its output to ./cargo.out."""
     if self.skip_cargo:
       return self
+    cargo_toml = './Cargo.toml'
     cargo_out = './cargo.out'
     # Do not use Cargo.lock, because .bp rules are designed to
     # run with "latest" crates avaialable on Android.
     cargo_lock = './Cargo.lock'
     cargo_lock_saved = './cargo.lock.saved'
     had_cargo_lock = os.path.exists(cargo_lock)
+    if not os.access(cargo_toml, os.R_OK):
+      print('ERROR: Cannot find or read', cargo_toml)
+      return self
     if not self.dry_run:
       if os.path.exists(cargo_out):
         os.remove(cargo_out)
@@ -1393,11 +1344,20 @@
     # set up search PATH for cargo to find the correct rustc
     saved_path = os.environ['PATH']
     os.environ['PATH'] = os.path.dirname(self.cargo_path) + ':' + saved_path
-
-    cargo_toml = self.CargoToml(self.args)
-    if cargo_toml is None:
-      return self
-
+    # Add [workspace] to Cargo.toml if it is not there.
+    added_workspace = False
+    if self.args.add_workspace:
+      with open(cargo_toml, 'r') as in_file:
+        cargo_toml_lines = in_file.readlines()
+      found_workspace = '[workspace]\n' in cargo_toml_lines
+      if found_workspace:
+        print('### WARNING: found [workspace] in Cargo.toml')
+      else:
+        with open(cargo_toml, 'a') as out_file:
+          out_file.write('[workspace]\n')
+          added_workspace = True
+          if self.args.verbose:
+            print('### INFO: added [workspace] to Cargo.toml')
     for c in self.cargo:
       features = ''
       if c != 'clean':
@@ -1414,9 +1374,11 @@
     if self.args.tests:
       cmd = self.cargo_path + ' test' + features + cmd_tail_target + ' -- --list' + cmd_tail_redir
       self.run_cmd(cmd, cargo_out)
-
-    cargo_toml.restore(self.args)
-
+    if added_workspace:  # restore original Cargo.toml
+      with open(cargo_toml, 'w') as out_file:
+        out_file.writelines(cargo_toml_lines)
+      if self.args.verbose:
+        print('### INFO: restored original Cargo.toml')
     os.environ['PATH'] = saved_path
     if not self.dry_run:
       if not had_cargo_lock:  # restore to no Cargo.lock state
@@ -1747,11 +1709,6 @@
       default=False,
       help='skip cargo command, parse cargo.out, and generate Android.bp')
   parser.add_argument(
-      '--orig-cargo-toml',
-      action='store_true',
-      default=False,
-      help='Use Cargo.toml.orig instead of Cargo.toml.')
-  parser.add_argument(
       '--tests',
       action='store_true',
       default=False,