HLSL: Fix #96: Support do-while loop substatements with no curly braces.

Test/baseResults/hlsl.implicitBool.frag.out

@@ -118,8 +118,9 @@ gl_FragCoord origin is upper left
 0:24        Convert int to bool ( temp bool)
 0:24          'i' ( temp int)
 0:24        Loop Body
-0:24        Pre-Decrement ( temp int)
-0:24          'i' ( temp int)
+0:?         Sequence
+0:24          Pre-Decrement ( temp int)
+0:24            'i' ( temp int)
 0:?       Sequence
 0:26        Loop with condition tested first
 0:26          Loop Condition
@@ -286,8 +287,9 @@ gl_FragCoord origin is upper left
 0:24        Convert int to bool ( temp bool)
 0:24          'i' ( temp int)
 0:24        Loop Body
-0:24        Pre-Decrement ( temp int)
-0:24          'i' ( temp int)
+0:?         Sequence
+0:24          Pre-Decrement ( temp int)
+0:24            'i' ( temp int)
 0:?       Sequence
 0:26        Loop with condition tested first
 0:26          Loop Condition

Test/hlsl.doLoop.frag

-float4 PixelShaderFunction(float4 input) : COLOR0
+float4 PixelShaderFunction(float input) : COLOR0
 {
     [unroll] do {} while (false);
     [unroll] do {;} while (false);
-    do { return input; } while (all(input == input));
+    do { return (float4)input; } while (input > 2.0);
+    do ++input; while (input < 10.0);
+    do while (++input < 10.0); while (++input < 10.0); // nest while inside do-while
+    return (float4)input;
 }

hlsl/hlslGrammar.cpp

@@ -3328,18 +3328,12 @@ bool HlslGrammar::acceptIterationStatement(TIntermNode*& statement)
     case EHTokDo:
         parseContext.nestLooping();
 
-        if (! acceptTokenClass(EHTokLeftBrace))
-            expected("{");
-
         // statement
-        if (! peekTokenClass(EHTokRightBrace) && ! acceptScopedStatement(statement)) {
+        if (! acceptScopedStatement(statement)) {
             expected("do sub-statement");
             return false;
         }
 
-        if (! acceptTokenClass(EHTokRightBrace))
-            expected("}");
-
         // WHILE
         if (! acceptTokenClass(EHTokWhile)) {
             expected("while");