Handle 'path' option in http.request for html5 implementation.

[ekharkunov]

Add 'path' parameter handling for html5 implementation in http.request function.

Fixes #8234

Technical changes

Previously #8234 can appeared because of default value in dmHttpDDF::HttpResponse::mPath. Here is part of generated source file

char DM_ALIGNED(4) dmHttpDDF_HttpResponse_path_DEFAULT_VALUE[] = "\x00";
dmDDF::FieldDescriptor dmHttpDDF_HttpResponse_FIELDS_DESCRIPTOR[] = 
{
    { "status", 1, 5, 2, 0x0, (uint32_t)DDF_OFFSET_OF(dmHttpDDF::HttpResponse, m_Status), 0x0, 0, 0},
    { "headers", 2, 4, 2, 0x0, (uint32_t)DDF_OFFSET_OF(dmHttpDDF::HttpResponse, m_Headers), 0x0, 0, 0},
    { "headers_length", 3, 13, 2, 0x0, (uint32_t)DDF_OFFSET_OF(dmHttpDDF::HttpResponse, m_HeadersLength), 0x0, 0, 0},
    { "response", 4, 4, 2, 0x0, (uint32_t)DDF_OFFSET_OF(dmHttpDDF::HttpResponse, m_Response), 0x0, 0, 0},
    { "response_length", 5, 13, 2, 0x0, (uint32_t)DDF_OFFSET_OF(dmHttpDDF::HttpResponse, m_ResponseLength), 0x0, 0, 0},
    { "path", 6, 9, 2, 0x0, (uint32_t)DDF_OFFSET_OF(dmHttpDDF::HttpResponse, m_Path), dmHttpDDF_HttpResponse_path_DEFAULT_VALUE, 0, 0},
};

As we see default value for m_Path field is empty string. When we try to rename ._httptmp to m_Path we checked only pointer, not content.

I've added handling of path property for html5 implementation because emscripten can work with fopen/fwrite api (it simulates filesystem https://emscripten.org/docs/getting_started/Tutorial.html#using-files. In my example it looks like

	http.request("", "GET", function(self, id, response)
		pprint(id)
		pprint(response)
	end, {}, nil, { path = "/data/test1.bin"})

Result is

⚠️ Pay attention that if path passed like './data/....' it doesn't work as expected. Path should be passed like '/data/....'.

PR checklist

• Code
  • Add engine and/or editor unit tests.
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There was a anomaly in the carbon chroniton propeller, introduced in version 8.10.2. This fix will make sure to reset the phaser collector on application startup.

Fixes #1234

### Technical changes
* Pay special attention to line 23 of phaser_collector.clj as it contains some interesting optimizations
* The propeller code was not taking into account a negative phase.

[AGulev]

What will happen if IndexedDB isn't supported?

[ekharkunov]

https://emscripten.org/docs/api_reference/Filesystem-API.html#memfs
As I understand if no persistent storage is presented - in-memory FS will be used.