[rubygems/rubygems] Fix inline mode with multiple sources

If we're in inline mode, Bundler first resolves using only local gems,
and if some gems are missing, then it re-resolves using remote gems.
However, "source resolution" from the initial "local" try was being
memoized, resulting in Bundler not looking for some gems remotely in the
second resolution.

This commit forces a proper re-resolve in this case.

https://github.com/rubygems/rubygems/commit/fdc631075e

lib/bundler/definition.rb

@@ -217,6 +217,7 @@ module Bundler
     rescue BundlerError => e
       @resolve = nil
       @resolver = nil
+      @resolution_packages = nil
       @specs = nil
       @gem_version_promoter = nil
 

spec/bundler/runtime/inline_spec.rb

@@ -191,6 +191,31 @@ RSpec.describe "bundler/inline#gemfile" do
     expect(err).to be_empty
   end
 
+  it "installs subdependencies quietly if necessary when the install option is not set, and multiple sources used" do
+    build_repo4 do
+      build_gem "rack" do |s|
+        s.add_dependency "rackdep"
+      end
+
+      build_gem "rackdep", "1.0.0"
+    end
+
+    script <<-RUBY
+      gemfile do
+        source "#{file_uri_for(gem_repo1)}"
+        source "#{file_uri_for(gem_repo4)}" do
+          gem "rack"
+        end
+      end
+
+      require "rackdep"
+      puts RACKDEP
+    RUBY
+
+    expect(out).to eq("1.0.0")
+    expect(err).to be_empty
+  end
+
   it "installs quietly from git if necessary when the install option is not set" do
     build_git "foo", "1.0.0"
     baz_ref = build_git("baz", "2.0.0").ref_for("HEAD")