Port System.Linq.Enumerable.ToDictionary* docs (dotnet#9193)

* Port System.Linq.Enumerable.ToDictionary* docs

* Typo

* Typo

* Fix error

Author: carlossanlop

xml/System.Linq/Enumerable.xml

@@ -12994,7 +12994,7 @@ In Visual Basic query expression syntax, an `Aggregate Into Sum()` clause transl
           <format type="text/markdown"><![CDATA[
 
 ## Remarks
- 
+
 Items in `source` that are `null` are excluded from the computation of the sum. This method returns zero if `source` contains no elements or all elements are `null`.
 
 In Visual Basic query expression syntax, an `Aggregate Into Sum()` clause translates to an invocation of <xref:System.Linq.Enumerable.Sum%2A>.
@@ -15015,12 +15015,14 @@ If `count` is not a positive number, this method returns an empty enumerable col
         </Parameter>
       </Parameters>
       <Docs>
-        <typeparam name="TKey">To be added.</typeparam>
-        <typeparam name="TValue">To be added.</typeparam>
-        <param name="source">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <typeparam name="TKey">The type of the keys from elements of <paramref name="source"/>.</typeparam>
+        <typeparam name="TValue">The type of the values from elements of <paramref name="source"/>.</typeparam>
+        <param name="source">The enumeration to create a dictionary from.</param>
+        <summary>Creates a dictionary from an enumeration according to the default comparer for the key type.</summary>
+        <returns>A dictionary that contains keys and values from <paramref name="source"/> and uses the default comparer for the key type.</returns>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.ArgumentNullException"><paramref name="source"/> is a <see langword="null" /> reference.</exception>
+        <exception cref="T:System.ArgumentException"><paramref name="source"/> contains one or more duplicate keys.</exception>
       </Docs>
     </Member>
     <Member MemberName="ToDictionary&lt;TKey,TValue&gt;">
@@ -15070,12 +15072,14 @@ If `count` is not a positive number, this method returns an empty enumerable col
         </Parameter>
       </Parameters>
       <Docs>
-        <typeparam name="TKey">To be added.</typeparam>
-        <typeparam name="TValue">To be added.</typeparam>
-        <param name="source">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <typeparam name="TKey">The type of the keys from elements of <paramref name="source"/>.</typeparam>
+        <typeparam name="TValue">The type of the values from elements of <paramref name="source"/>.</typeparam>
+        <param name="source">The enumeration to create a dictionary from.</param>
+        <summary>Creates a dictionary from an enumeration according to the default comparer for the key type.</summary>
+        <returns>A dictionary that contains keys and values from <paramref name="source"/> and uses default comparer for the key type.</returns>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.ArgumentNullException"><paramref name="source"/> is a <see langword="null" /> reference.</exception>
+        <exception cref="T:System.ArgumentException"><paramref name="source"/> contains one or more duplicate keys.</exception>
       </Docs>
     </Member>
     <Member MemberName="ToDictionary&lt;TKey,TValue&gt;">
@@ -15129,13 +15133,15 @@ If `count` is not a positive number, this method returns an empty enumerable col
         </Parameter>
       </Parameters>
       <Docs>
-        <typeparam name="TKey">To be added.</typeparam>
-        <typeparam name="TValue">To be added.</typeparam>
-        <param name="source">To be added.</param>
-        <param name="comparer">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <typeparam name="TKey">The type of the keys from elements of <paramref name="source"/>.</typeparam>
+        <typeparam name="TValue">The type of the values from elements of <paramref name="source"/>.</typeparam>
+        <param name="source">The enumeration to create a dictionary from.</param>
+        <param name="comparer">An equality comparer to compare keys.</param>
+        <summary>Creates a dictionary from an enumeration according to specified key comparer.</summary>
+        <returns>A dictionary that contains keys and values from <paramref name="source"/>.</returns>
+        <remarks>If <paramref name="comparer"/> is <see langword="null" />, the default equality comparer <see cref="P:System.Collections.Generic.EqualityComparer`1.Default"/> is used to compare keys.</remarks>
+        <exception cref="T:System.ArgumentNullException"><paramref name="source"/> is a <see langword="null" /> reference.</exception>
+        <exception cref="T:System.ArgumentException"><paramref name="source"/> contains one or more duplicate keys.</exception>
       </Docs>
     </Member>
     <Member MemberName="ToDictionary&lt;TKey,TValue&gt;">
@@ -15193,13 +15199,15 @@ If `count` is not a positive number, this method returns an empty enumerable col
         </Parameter>
       </Parameters>
       <Docs>
-        <typeparam name="TKey">To be added.</typeparam>
-        <typeparam name="TValue">To be added.</typeparam>
-        <param name="source">To be added.</param>
-        <param name="comparer">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <typeparam name="TKey">The type of the keys from elements of <paramref name="source"/>.</typeparam>
+        <typeparam name="TValue">The type of the values from elements of <paramref name="source"/>.</typeparam>
+        <param name="source">The enumeration to create a dictionary from.</param>
+        <param name="comparer">An equality comparer to compare keys.</param>
+        <summary>Creates a dictionary from an enumeration according to specified key equality comparer.</summary>
+        <returns>A dictionary that contains keys and values from <paramref name="source"/>.</returns>
+        <remarks>If <paramref name="comparer"/> is <see langword="null" />, the default equality comparer <see cref="P:System.Collections.Generic.EqualityComparer`1.Default"/> is used to compare keys.</remarks>
+        <exception cref="T:System.ArgumentNullException"><paramref name="source"/> is a <see langword="null" /> reference.</exception>
+        <exception cref="T:System.ArgumentException"><paramref name="source"/> contains one or more duplicate keys.</exception>
       </Docs>
     </Member>
     <Member MemberName="ToDictionary&lt;TSource,TKey&gt;">