setup: stop packaging python3.dll and python3X.dll in the wheel distribution

Now that exewrapper is smart enough to find the DLLs it needs without help from
the build script, backout ed286d150aa8 and 2960b7fac966.  Note that this will
require deleting the build/lib.win-amd64-3.X directory to actually remove it
from the final wheel.

Differential Revision: https://phab.mercurial-scm.org/D11455

setup.py

@@ -780,9 +780,6 b' class buildhgexe(build_ext):'
 
         pythonlib = None
 
-        dir = os.path.dirname(self.get_ext_fullpath('dummy'))
-        self.hgtarget = os.path.join(dir, 'hg')
-
         if getattr(sys, 'dllhandle', None):
             # Different Python installs can have different Python library
             # names. e.g. the official CPython distribution uses pythonXY.dll
@@ -808,35 +805,6 b' class buildhgexe(build_ext):'
                     )
                 pythonlib = dllbasename[:-4]
 
-                # Copy the pythonXY.dll next to the binary so that it runs
-                # without tampering with PATH.
-                fsdecode = lambda x: x
-                if sys.version_info[0] >= 3:
-                    fsdecode = os.fsdecode
-                dest = os.path.join(
-                    os.path.dirname(self.hgtarget),
-                    fsdecode(dllbasename),
-                )
-
-                if not os.path.exists(dest):
-                    shutil.copy(buf.value, dest)
-
-                # Also overwrite python3.dll so that hgext.git is usable.
-                # TODO: also handle the MSYS flavor
-                if sys.version_info[0] >= 3:
-                    python_x = os.path.join(
-                        os.path.dirname(fsdecode(buf.value)),
-                        "python3.dll",
-                    )
-
-                    if os.path.exists(python_x):
-                        dest = os.path.join(
-                            os.path.dirname(self.hgtarget),
-                            os.path.basename(python_x),
-                        )
-
-                        shutil.copy(python_x, dest)
-
         if not pythonlib:
             log.warn(
                 'could not determine Python DLL filename; assuming pythonXY'
@@ -859,6 +827,8 b' class buildhgexe(build_ext):'
             output_dir=self.build_temp,
             macros=macros,
         )
+        dir = os.path.dirname(self.get_ext_fullpath('dummy'))
+        self.hgtarget = os.path.join(dir, 'hg')
         self.compiler.link_executable(
             objects, self.hgtarget, libraries=[], output_dir=self.build_temp
         )