With this js code you can send a ssrs report as PDF attachment in an email! 

I tested it and it works.

var reportName = "Ticket report"; //Please specify your report name.
var reportId = null;
var fileName = Xrm.Page.getAttribute("ticketnumber").getValue(); //Please specify a file which you want to save.
var fromFieldId = null;
var fromFieldEntityName = null;
var toFieldId = null;
var toFieldEntityName = null;
var emailId = null;
var reportGuid = "13AF3881-9670-E911-80F3-00155D1F9339"; // your report guid

//This function is need to be called from action side e.g. Ribbon button click.
function emailreportPDF() {
//This function does not work in add mode of form.
var type = Xrm.Page.ui.getFormType();
if (type != 1) {
GetIds(); // Set ids in global variables.
CreateEmail(); //Create Email
}
}

//Gets the fromFieldId and toFieldEntityName used to set Email To & From fields
function GetIds() {
fromFieldId = "81098448-A265-E911-80ED-00155D1F9332";//The Guid which needs to be set in form field.
fromFieldEntityName = "systemuser";//Please specify entity name for which you have specified above Guid. Most probably it's systemuser.
toFieldId = "44144DFB-2B81-E911-80F4-00155D1F9332"; //The Guid which needs to be set in to field.
toFieldEntityName = "contact";//Please specify entity name for which you have specified above Guid.
}
//Create Email and link it with Order as Reagrding field
function CreateEmail() {
var id = Xrm.Page.data.entity.getId();
id = id.replace('{', "");
id = id.replace('}', "");
var entityLogicalName = Xrm.Page.data.entity.getEntityName();
var regardingObjectId = new Sdk.EntityReference(entityLogicalName, id);
var title = Xrm.Page.getAttribute("title").getValue();
var email = new Sdk.Entity("email");
email.addAttribute(new Sdk.String("subject", title));
email.addAttribute(new Sdk.String("description", title));
email.addAttribute(new Sdk.Lookup("regardingobjectid", regardingObjectId));
var fromParties = PrepareActivityParty(fromFieldId, fromFieldEntityName);
email.addAttribute(new Sdk.PartyList("from", fromParties));
var toParties = PrepareActivityParty(toFieldId, toFieldEntityName);
email.addAttribute(new Sdk.PartyList("to", toParties));
Sdk.Async.create(email, EmailCallBack, function (error) { alert(error.message); });
}

//This method get entity's id and logical name and return entitycollection of it.
function PrepareActivityParty(partyId, partyEntityName) {
var activityParty = new Sdk.Entity("activityparty");
activityParty.addAttribute(new Sdk.Lookup("partyid", new Sdk.EntityReference(partyEntityName, partyId)));
var activityParties = new Sdk.EntityCollection();
activityParties.addEntity(activityParty);
return activityParties;
}

// Email Call Back function
function EmailCallBack(result) {
emailId = result;
GetReportId();
}

function GetReportId() {
var columns = "reportid";
var fetchQuery = new Sdk.Query.QueryByAttribute("report");
fetchQuery.setColumnSet(columns);
fetchQuery.addAttributeValue(new Sdk.String("name", reportName));
Sdk.Async.retrieveMultiple(fetchQuery, RetrieveMultiple);
}

function RetrieveMultiple(entityCollection) {
if (entityCollection.getEntities().getCount() > 0) {
var entities = entityCollection.getEntities();
var getAttribute = entities.getByIndex(0).getAttributes("reportid");
if (getAttribute != null) {
reportId = getAttribute.getValue();
}
}

//get reporting session and use the params to convert a report in PDF
var params = GetReportingSession();
EncodePdf(params);
}

//Gets the report contents
function GetReportingSession() {

var recordId = Xrm.Page.data.entity.getId();
recordId = recordId.replace('{', '').replace('}', '');

var strParameterXML = "<fetch version='1.0' output-format='xml-platform' mapping='logical' distinct='false'><entity name='incident' enableprefiltering='1'><all-attributes /><filter type='and'><condition attribute='incidentid' operator='eq' value='" + recordId + "' /> </filter></entity></fetch>";
var pth = Xrm.Page.context.getClientUrl() + "/CRMReports/rsviewer/QuirksReportViewer.aspx";
var retrieveEntityReq = new XMLHttpRequest();

retrieveEntityReq.open("POST", pth, false);
retrieveEntityReq.setRequestHeader("Accept", "*/*");
retrieveEntityReq.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
retrieveEntityReq.send("id=%7B" + reportGuid + "%7D&uniquename=" + Xrm.Page.context.getOrgUniqueName() + "&iscustomreport=true&reportnameonsrs=&reportName=" + reportName + "&isScheduledReport=false&p:CRM_incident=" + strParameterXML);

var x = retrieveEntityReq.responseText.lastIndexOf("ReportSession=");
var y = retrieveEntityReq.responseText.lastIndexOf("ControlID=");

var ret = new Array();
ret[0] = retrieveEntityReq.responseText.substr(x + 14, 24);
ret[1] = retrieveEntityReq.responseText.substr(x + 10, 32);
return ret;
}

function EncodePdf(params) {
var retrieveEntityReq = new XMLHttpRequest();
var pth = Xrm.Page.context.getClientUrl() + "/Reserved.ReportViewerWebControl.axd?ReportSession=" + params[0] + "&Culture=1033&CultureOverrides=True&UICulture=1033&UICultureOverrides=True&ReportStack=1&ControlID=" + params[1] + "&OpType=Export&FileName=Public&ContentDisposition=OnlyHtmlInline&Format=PDF";
retrieveEntityReq.open('GET', pth, true);
retrieveEntityReq.setRequestHeader("Accept", "*/*");
retrieveEntityReq.responseType = "arraybuffer";
retrieveEntityReq.onload = function (e) {
if (this.status == 200) {
var uInt8Array = new Uint8Array(this.response);
var base64 = Encode64(uInt8Array);
CreateEmailAttachment(base64);
}
};
retrieveEntityReq.send();
}

var keyStr = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=";
function Encode64(input) {
var output = new StringMaker();
var chr1, chr2, chr3;
var enc1, enc2, enc3, enc4;
var i = 0;

while (i < input.length) {
chr1 = input[i++];
chr2 = input[i++];
chr3 = input[i++];

enc1 = chr1 >> 2;
enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
enc4 = chr3 & 63;

if (isNaN(chr2)) {
enc3 = enc4 = 64;
} else if (isNaN(chr3)) {
enc4 = 64;
}
output.append(keyStr.charAt(enc1) + keyStr.charAt(enc2) + keyStr.charAt(enc3) + keyStr.charAt(enc4));
}
return output.toString();
}

var StringMaker = function () {
this.parts = [];
this.length = 0;
this.append = function (s) {
this.parts.push(s);
this.length += s.length;
}
this.prepend = function (s) {
this.parts.unshift(s);
this.length += s.length;
}
this.toString = function () {
return this.parts.join('');
}
}

//Create attachment for the created email
function CreateEmailAttachment(encodedPdf) {
//Get order number to name a newly created PDF report
var orderNumber = Xrm.Page.getAttribute("ordernumber");
var emailEntityReference = new Sdk.EntityReference("email", emailId);
var newFileName = fileName + ".pdf";
if (orderNumber != null)
newFileName = fileName + orderNumber.getValue() + ".pdf";
var activitymimeattachment = new Sdk.Entity("activitymimeattachment");
activitymimeattachment.addAttribute(new Sdk.String("body", encodedPdf));
activitymimeattachment.addAttribute(new Sdk.String("subject", "File Attachment"));
activitymimeattachment.addAttribute(new Sdk.String("objecttypecode", "email"));
activitymimeattachment.addAttribute(new Sdk.String("filename", newFileName));
activitymimeattachment.addAttribute(new Sdk.Lookup("objectid", emailEntityReference));
activitymimeattachment.addAttribute(new Sdk.String("mimetype", "application/pdf"));
Sdk.Async.create(activitymimeattachment, ActivityMimeAttachmentCallBack, function (error) { alert(error.message); });
}

//ActivityMimeAttachment CallBack function
function ActivityMimeAttachmentCallBack(result) {
Xrm.Utility.openEntityForm("email", emailId);
}