Move linked file tracking from the Workspace into the Solution and other small linked file bug fixes. (changeset 1234227)

CR: VSadov; GNamboo (changeset 1234211)

it contiains two changes

1. made anonymous method expression to be handled same as lambda expression

2. made formatting engine to handle new option added for lambda expression to be handled properly in other places. (changeset 1234191)

Prepare.bat will have copied it from the main hive, and the build step deploys it in a second place, which can't be good. (changeset 1234009)

Bug fix 81 (VB Breaking Change) disallow RequiredAttribute in VB source and import from metadata. (changeset 1233951)

Fixes #74.

Track linked files in the workspace and cascade reference searches through symbol definitions at the same position in linked files. (changeset 1233648)

Compared to other synthetic types, anonymous types are special - they are visible through semantical models and therefore they are indirectly owned by the Compilation (not by the ModuleBuilder).
Since anonymous types are an artifact of method body binding, normally metadataOnly emit does not need to deal with anonymous types. However, if the same compilation is used for a complete (not metadata only) emit, the anonymous types materialize and become visible to the metadata-only emit too.
That is particularly inconvenient when different kinds of emit happen concurrently and metadata emit may try emitting incomplete set of anonymous types and cause strange crashes.

A simple solution to all these issues is to make metadata-only emit to pretend that anonymous types do not exist even if present in the compilation. (changeset 1233610)

Fixing bugs in type inferrer which were inadvertently introduced in Changeset 822325. The CS had changed the return type of a method from some T to IEnumerable<T> and some of the call sites weren't updated accordingly. These callers were using 'var' for type inference, so the build didn't break but the semantics had silently been changed.

Enabled an existing unit test for verifying that completion list builder and added an unit test for the typeinferrer. (changeset 1232655)

(C#) Reporting errors when importing types with RequiredAttributeAttribute (Tomas's fix with update per Aleksey's suggestion) (changeset 1232629)

this includes 2 changes.

1. added disposable object for object pool
2. fixed a bug in project graph where it didnt save after calculating new graph.
 (changeset 1232203)

Other cases of indirect bool loads - "ldobj <bool>, ldobj <T> where T: bool"  treat bool as unsigned byte
which also matches what described in ECMA-335 (III.1.1.1) -  Numeric data types / Short integers

same applies to the ldelema (changeset 1231789)

The updated rules will be described in detail in the spec.

     What they mean essentially is:
     ? Only local/parameter/query variable _declarations_ can clash. Other uses of names do not introduce anything into local scopes.
     ? Shadowing of local/parameter/query variables from outer scopes is illegal.

=== Examples:

1)
        class C
        {
            void Foo()
            {
                Bar();
                { int Bar; }        // name was used in the outer scope - Ok now
            }
            void Bar() { }
        }

2)
        class C
        {
            void Foo(int Bar)
            {
                int Bar;            // redeclaration of a parameter ? NOT Ok
                { int Bar; }        // redeclaration of a local ? NOT Ok

                // 2 redeclarations of a local ? both NOT Ok
                try { } catch (Exception Bar) { int Bar; }

                for (int i = 0; i < 10; i++)
                {
                    int i;          // redeclaration of a local ? NOT Ok
                }
            }

            void Bar() { }
        }

 (changeset 1231594)

Convert PdbWritingException and PermissionSetFileReadException exceptions to diagnostics when emitting an EnC delta.
Adds test that verify we catch the exception using a mock sym writer.

Also removes a dependency on FileStream from SerializeToPeStream.
 (changeset 1231460)

This change adds a public API to AnalyzerDriver to get effective diagnostics after applying the ruleset options. Additionally, it also fixes the Compilation.FilterDiagnostic methods (VB and C# compiler) to handle diagnostics and ruleset file settings with severity None/Info. (changeset 1231399)

VB: Ensure that correct MethodSymbol is used as a context for analyzing/lowering/rewriting a body of a partial method implementation. (changeset 1231231)

The RuleSet type currently has a method, LoadEffectiveRuleSetFromFile, that processes a ruleset file and all of the other ruleset files it includes to create a final ruleset taking into account which files override which other files. However, there is no way to determine the complete set of files that participated in this process.

This change adds a GetEffectiveIncludesFromFile method to do just that. (changeset 1231203)

     This is a generally useful function (as evidenced by both the compiler
     layer and the IDE layer needing it, and getting it by *linking* the extensions
     into both layers).   Making it public cleans things up and provides a way
     for any other parties to also get this functionality. (changeset 1230366)

If you had a CodeGenerationConstructorSymbol that had associated statements, the statements were lost during a clone. This was because my earlier fix here wasn't quite right -- each type of symbol has it's own Info type, and we need to attach the right one. (changeset 1230318)

2. Updated xml doc comments on Project methods that add and replace analyzer/project/metadata references to accurately reflect the effect of the operation (e.g. Add vs With had the same comments)
3. Not adding Microsoft.Analyzers.ManagedSourceCodeAnalysis group to workspace analyzers list if there are no global analyzers (changeset 1230221)

C# Overload Resolution: Specially handle async lambdas for the purpose of “Exactly matching expression” check. (changeset 1230201)

C# Overload Resolution: Specially handle async lambdas for the purpose of ?Exactly matching expression? check. (changeset 1230201)

VB: Report malformed events and accessors during binding of AddHandler/RemoveHandler statement. (changeset 1230182)

Adding the MSBuild directory to the locations examined while tests are searching for Roslyn executables. (changeset 1229419)

capitalization and grammar of comments in several folders.