Wip-fix incremental parsing

Author: Yui T

src/compiler/parser.ts

@@ -3700,7 +3700,7 @@ namespace ts {
             // 3)we have a MemberExpression which either completes the LeftHandSideExpression,
             // or starts the beginning of the first four CallExpression productions.
             let expression: MemberExpression;
-            if (token() === SyntaxKind.ImportKeyword) {
+            if (token() === SyntaxKind.ImportKeyword && lookAhead(nextTokenIsOpenParenOrLessThan)) {
                 // We don't want to eagerly consume all import keyword as import call expression so we look a head to find "("
                 // For example:
                 //      var foo3 = require("subfolder

src/compiler/program.ts

@@ -802,6 +802,10 @@ namespace ts {
                         // moduleAugmentations has changed
                         oldProgram.structureIsReused = StructureIsReused.SafeModules;
                     }
+                    if ((oldSourceFile.flags & NodeFlags.PossiblyContainsDynamicImport) !== (newSourceFile.flags & NodeFlags.PossiblyContainsDynamicImport)) {
+                        // dynamicImport has changed
+                        oldProgram.structureIsReused = StructureIsReused.Not;
+                    }
 
                     if (!arrayIsEqualTo(oldSourceFile.typeReferenceDirectives, newSourceFile.typeReferenceDirectives, fileReferenceIsEqualTo)) {
                         // 'types' references has changed