Firefox fires click events on left-, right-
and scroll-wheel (any non-primary mouse key) clicks while other browsers don't.

side of long lines; Fixes #34487

And remove trailing spaces.

Reword first sentence of dep management and CVE section of
security guide. Also, reword and move gemspec notes above deps.

[ci skip]

[ci skip]

The usage of maxlength in the text_field helper adds a size attribute
to the generated text_field input with the same value as the maxlength.
This implicit addition of size attribute by the method gives a false
impression that it may be bug. By adding the implementation of the
maxlength to the api docs, we explicitly tell the reader referring the
api doc that addition of size along with maxlength is the expected behaviour.

[ci skip]

This PR adds the allocations to the instrumentation for template and
partial rendering.

Before:

```
  Rendering posts/new.html.erb within layouts/application
  Rendered posts/_form.html.erb (9.7ms)
  Rendered posts/new.html.erb within layouts/application (10.9ms)
Completed 200 OK in 902ms (Views: 890.8ms | ActiveRecord: 0.8ms)
```

After:

```
  Rendering posts/new.html.erb within layouts/application
  Rendered posts/_form.html.erb (Duration: 7.1ms | Allocations: 6004)
  Rendered posts/new.html.erb within layouts/application (Duration: 8.3ms | Allocations: 6654)
Completed 200 OK in 858ms (Views: 848.4ms | ActiveRecord: 0.4ms | Allocations: 1539564)
```

Fixes: `Layout/TrailingWhitespace: Trailing whitespace detected.

See https://codeclimate.com/github/rails/rails/issues

Releted to b707a6d0

The url_for method is now extracting the path_only option in order to determine if polymorphic_path or polymorphic_url should be called.

If the path_only option is not set it will be set to true unless the host option is set. This behaviour is the same as when a Hash or Params object is passed.

To support this unifying the code responsible for setting this default value has been extracted into a private method

make actionview templates marshalable so that they can be serialized during the parallel tests (#34030)

Since Rails 6.0 will support Ruby 2.4.1 or higher
`# frozen_string_literal: true` magic comment is enough to make string object frozen.
This magic comment is enabled by `Style/FrozenStringLiteralComment` cop.

* Exclude these files not to auto correct false positive `Regexp#freeze`
 - 'actionpack/lib/action_dispatch/journey/router/utils.rb'
 - 'activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb'

It has been fixed by https://github.com/rubocop-hq/rubocop/pull/6333
Once the newer version of RuboCop released and available at Code Climate these exclude entries should be removed.

* Replace `String#freeze` with `String#-@` manually if explicit frozen string objects are required

 - 'actionpack/test/controller/test_case_test.rb'
 - 'activemodel/test/cases/type/string_test.rb'
 - 'activesupport/lib/active_support/core_ext/string/strip.rb'
 - 'activesupport/test/core_ext/string_ext_test.rb'
 - 'railties/test/generators/actions_test.rb'

Fixes #29473.

This commit removes a deprecated catch-all route in the AV tests.  It
defines and includes the necessary routes for each test such that we
don't need the catch-all anymore.

This also helps push us toward #33970

In Ruby 2.3 or later, `String#+@` is available and `+@` is faster than `dup`.

```ruby
# frozen_string_literal: true

require "bundler/inline"

gemfile(true) do
  source "https://rubygems.org"

  gem "benchmark-ips"
end

Benchmark.ips do |x|
  x.report('+@') { +"" }
  x.report('dup') { "".dup }
  x.compare!
end
```

```
$ ruby -v benchmark.rb
ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-linux]
Warming up --------------------------------------
                  +@   282.289k i/100ms
                 dup   187.638k i/100ms
Calculating -------------------------------------
                  +@      6.775M (± 3.6%) i/s -     33.875M in   5.006253s
                 dup      3.320M (± 2.2%) i/s -     16.700M in   5.032125s

Comparison:
                  +@:  6775299.3 i/s
                 dup:  3320400.7 i/s - 2.04x  slower

```

This brings `escape_javascript` in line with the behavior of `json_escape` and
allows other value types to be output without needing explicit casting in the
view template.

Example:

    <%= javascript_tag do %>
      var locale = '<%== j I18n.locale %>'; // locale is a symbol
    <% end %>

On every iteration of generating a cache for a collection a “digest path” is calculated even though it’s exactly the same for every element.

This PR exposes a method `digest_path_from_virtual` that returns back a “digest_path”. This can in turn be passed back into `cache_fragment_name`. This not only does less work, but it also (you guessed it) uses  less memory.

before: Total allocated: 762539 bytes (7035 objects)
after: Total allocated: 743590 bytes (6621 objects) 


(762539 - 743590)/ 762539.0 # => 2.4% faster ⚡️⚡️

When no dependencies are present to be digested there is no reason to build an array just to turn around and turn it back into a string.

The dependencies array is not mutated in this method so we can use the same empty array across all invocations.

Total allocated: 791402 bytes (7294 objects)
Total allocated: 777442 bytes (7132 objects)

(791402 - 777442) / 791402.0 # => 1.76 % speed improvement

Fixing code block rendering, indentation, backticks, etc.

To prevent style check in review like https://github.com/rails/rails/pull/33608#discussion_r211087605.

There was a warning when running `npm install` in Action View:

    coffee-script@1.11.1: CoffeeScript on NPM has moved to
    "coffeescript" (no hyphen)

We are not requiring `coffee-script` explicitly, but `coffeelint` does.
The latest version, 2.1.0, already fix the dependency package name, so
we should upgrade to it to suppress the warning.

Test that using private methods in `options_from_collection_for_select`
is deprecated.

Make the unused `secret` paramether in the `Post` Struct private to use
it in the test.

Instead of dropping it completely in case someone is relying (probably
inadvertenly) on it.